67486 + Interview Questions in Secondary School in Physics

1.	Name two factors on which the heat energy liberated by a body on cooling depends.plz answer it...
Answer» There are many factors on which the LIBERATED HEAT energy from a body by cooling it,depends: 1)The amount of heat energy stored in that particular matter.The MATHEMATICAL formula of the gained heat energy is: H=mst . 2)The amount of heat in the surrounding's ATMOSPHERE of that object which is liberating heat. 3)The intensity of the cooling process. And many more...

1.

Name two factors on which the heat energy liberated by a body on cooling depends.plz answer it...

Answer»

There are many factors on which the LIBERATED HEAT energy from a body by cooling it,depends:

1)The amount of heat energy stored in that particular matter.The MATHEMATICAL formula of the gained heat energy is:

H=mst .

2)The amount of heat in the surrounding's ATMOSPHERE of that object which is liberating heat.

3)The intensity of the cooling process.

And many more...

Discussion

2.	What were the three major observations Rutherford made in the gold foil experiment?
Answer» *The three major Observations made by the Rutherford in the GOLD foil experiments are ⇒* 1. Most of the ALPHA Particles (nearly 99%) passed through the gold foil undeflected. 2. A small Fraction of the alpha PARTICIPLES get deflected through small angles. 3. Very Few(about 1 in 20,000) did not pass through the foil at all but SUFFERED large deflections (more than 90 %) or even come back suffering the deflections of 180°. *Hope it helps.*

2.

What were the three major observations Rutherford made in the gold foil experiment?

Answer»

The three major Observations made by the Rutherford in the GOLD foil experiments are ⇒

1. Most of the ALPHA Particles (nearly 99%) passed through the gold foil undeflected.

2. A small Fraction of the alpha PARTICIPLES get deflected through small angles.

3. Very Few(about 1 in 20,000) did not pass through the foil at all but SUFFERED large deflections (more than 90 %) or even come back suffering the deflections of 180°.

Hope it helps.

Discussion

3.	In a stethoscope, sound of heart beats travel through stethoscopes tube,Pick the correct answer.A) By bending along the tube B) In a straight lineC) Undergoing multiple reflections D) all of the above
Answer» It is C ...the ANSWER should be c only

Discussion

4.	Differance between electric cinductors and insulator
Answer» ELECTRIC conductor is material that allows easy FLOW of current . Its resistance is very low . INSULATOR is a material with high resistance that doesn't allow the easy flow of current through it.

Discussion

5.	The torque of the weight of a body about any vertical axis is zero. Is it always correct?
Answer»

Discussion

6.	Kitchen gas burner are often coated with chromium Why
Answer» We OFTEN find a chromium plating on KITCHEN gas burners which not only provide Shiny appearance but also helps to avoid CORROSION and EFFECTS of WEAR and tear and scratches. some coatings have to increase the strength of the base metal . hope it helps....

Discussion

7.	A ball of mass m moving at a speed v makes a head-on collision with an identical ball at rest. The kinetic energy of the balls after the collision is three fourths of the original. Find the coefficient of restitution.
Answer» Thanks for asking the question! ANSWER:: Mass of FIRST ball = m Speed of first ball = v Mass of SECOND ball = m Let final velocities of first and second ball are v₁ and v₂ respectively. Using law of conservation of momentum, m(v₁ + v₂) = mv v₁ + v₂ = v Equation 1 And , v₁ - v₂ = ev Equation 2 Given:- Final KINETIC Energy = 3/4 Initial Kinetic Energy (1/2)mv₁² + (1/2)mv₂² = (3/4) x 1/2 mv² v₁² + v₂² = (3/4) v² [(v₁ + v₂)² + (v₁ - v₂)² ] / 2 = 3v² / 4 (1 + e²)v² / 2 = 3v² / 4 1 + e² = 3/2 e² = 1/2 e = 1 / √2 Hope it helps!

7.

A ball of mass m moving at a speed v makes a head-on collision with an identical ball at rest. The kinetic energy of the balls after the collision is three fourths of the original. Find the coefficient of restitution.

Answer»

Thanks for asking the question!

ANSWER::

Mass of FIRST ball = m

Speed of first ball = v

Mass of SECOND ball = m

Let final velocities of first and second ball are v₁ and v₂ respectively.

Using law of conservation of momentum,

m(v₁ + v₂) = mv

v₁ + v₂ = v Equation 1

And , v₁ - v₂ = ev Equation 2

Given:-

Final KINETIC Energy = 3/4 Initial Kinetic Energy

(1/2)mv₁² + (1/2)mv₂² = (3/4) x 1/2 mv²

v₁² + v₂² = (3/4) v²

[(v₁ + v₂)² + (v₁ - v₂)² ] / 2 = 3v² / 4

(1 + e²)v² / 2 = 3v² / 4

1 + e² = 3/2

e² = 1/2

e = 1 / √2

Hope it helps!

Discussion

8.	If a hole is bored along a diameter of the earth and a stone is dropped into the hole it will
Answer» I THINK that there will no GRAVITY by drilling a HOLE in the earth so the stone will float

Discussion

9.	Because of the friction between the water in oceans with the earth's surface, the rotational kinetic energy of the earth is continuously decreasing. If the earth's angular speed decreases by 0.0016 rad/day in 100 years, find the average torque of the friction on the earth. Radius of the earth is 6400 km and its mass is 6.0 x 10²⁴ kg. ?
Answer» Given in the question :- Angular speed is decrease by 0.0016 rad / day in 100 years. *Time t = 100 yrs.* or time in terms of day t, = 100 × 365 = 36500 day. ω(Initial) = 2 π rad /day ω'(FINAL) = 2 π - 0.0016 rad /day *Now, we have to FIND* $\alpha$ *= ?* Now we know the formula , $\omega' = \omega - \alpha t$ *Now put the given value in this formula* 2 π- 0.0016 = 2 π - α × 36500. $\alpha = \frac{0.0016}{36500}$ $\alpha = 4.4 * 10^-^8 rad/day^2$ α = 4.4 x 10⁻⁸ × (24 × 3600²) [on changing into sec] $\alpha = 5.87 * 10^-^1^8 rad/s^2$ *Here given that the Moment of inertia of the earth* $= \frac{2}{5} MR^2$ = 0.40 × 6.0 × 10²⁴ × 6400000² = 9.8 x 10³⁷ Average torque produce by the ocean of the FRICTION force = Iα = 9.83 x 10³⁷ × 5.87 x 10⁻¹⁸ $\boxed{5.77 * 10^2^0 N.m}$ = *Hope it Helps :-)*

9.

Because of the friction between the water in oceans with the earth's surface, the rotational kinetic energy of the earth is continuously decreasing. If the earth's angular speed decreases by 0.0016 rad/day in 100 years, find the average torque of the friction on the earth. Radius of the earth is 6400 km and its mass is 6.0 x 10²⁴ kg. ?

Answer»

Given in the question :-

Angular speed is decrease by 0.0016 rad / day in 100 years.

Time t = 100 yrs.

or time in terms of day t, = 100 × 365 = 36500 day.

ω(Initial) = 2 π rad /day

ω'(FINAL) = 2 π - 0.0016 rad /day

Now, we have to FIND $\alpha$ = ?

Now we know the formula ,

$\omega' = \omega - \alpha t$

Now put the given value in this formula

2 π- 0.0016 = 2 π - α × 36500.

$\alpha = \frac{0.0016}{36500}$

$\alpha = 4.4 * 10^-^8 rad/day^2$

α = 4.4 x 10⁻⁸ × (24 × 3600²) [on changing into sec]

$\alpha = 5.87 * 10^-^1^8 rad/s^2$

Here given that the Moment of inertia of the earth

$= \frac{2}{5} MR^2$

= 0.40 × 6.0 × 10²⁴ × 6400000²

= 9.8 x 10³⁷

Average torque produce by the ocean of the FRICTION force = Iα

= 9.83 x 10³⁷ × 5.87 x 10⁻¹⁸

$\boxed{5.77 * 10^2^0 N.m}$ =

Hope it Helps :-)

Discussion

10.	A boy throws a ball in a train moving at a speed of 18 km/h with a velocity of
Answer» WRITE FULL QUESTION then i will GIVE ANSWER

Discussion

11.	Colour of methyl orange in alkali conditions? [ ]a) orangeb) yellow c) redd) blue
Answer» YELLOW is the answer hope it HELPS you

Discussion

12.	Write the steps you would use for making tea. Use the words given below and write the steps for making tea? Solution, solvent, solute, dissolve, soluble, insoluble, filtrate and residue.
Answer» For making tea , various steps are : (i) put some water (e.g., solvent) in pan and put the pan containing water on a lighted gas burner. (ii) after some time water begins to boil. now add appropriate amount of MILK(e.g., solute) and sugar (e.g., solute). (iii) now stir the contents of pan with the help of tea spoon. the sugar(solute) being soluble in water will dissolve and milk(solute) will become miscible with water(solvent) a solution is thus FORMED. (iv) on further boiling solution, solute (sugar) gets completely dissolved. (v) now appropriate amount of leaves (solute)to the above solution in the pan. tea leaves are insoluble in the solution. boil the solution and filter through a SEIVE.tea will be COLLECTED as filtrate and tea leaves will get collected on seive as RESIDUE.

Discussion

13.	What is the unit of relaxation time (tau)?
Answer» S. is the UNIT of the RELAXATION TIME

Discussion

14.	a grinding wheel of mass 5.0kg and diameter 0.4 m is rotating with an angular speed of 2 rev S-1,calculate the torque which will increase its angular speed to 8 revolution per second in 2s.
Answer» torque=moment of INERTIA* alpha alpha= 8-2/2=3rev/s moment of inertia(if CONSIDERED RING)=mr^2=50.2^2=0.2 units torque=0.23=0.6 NM

14.

a grinding wheel of mass 5.0kg and diameter 0.4 m is rotating with an angular speed of 2 rev S-1,calculate the torque which will increase its angular speed to 8 revolution per second in 2s.

Answer»

torque=moment of INERTIA* alpha

alpha= 8-2/2=3rev/s

moment of inertia(if CONSIDERED RING)=mr^2=5*0.2^2=0.2 units

torque=0.2*3=0.6 NM

Discussion

15.	What is electric motor state its principale and give its uses
Answer» Definition - The device which converts electrical energy into mechanical energy is called Electric Motor. Principle - Electric Motor works on the principal that A current carrying conductors placed in a MAGNETIC field experiences a force. Structure: Here, A rectangular loop ABCD of COPPER wire with resistive COATING is placed between the North Pole and South Pole of a strong magnet { Horseshoe magnet } such that the branches AB and CD are perpendicular to the direction of the magnetic field. The ends of the loop are connected to the two halves , X and Y , of split rings - X and Y have resistive coating on their inner surfaces and are tightly fitted to the axle. The outer conducting surfaces of X and Y are in contact with the two stationary brushes , E and F , respectively. Working: When the circuit is completed with the plug key or switch the current flows in the direction E ➡️A➡️B➡️C➡️D➡️ F. As the magnetic field is directed from the north pole to the South Pole the force on AB is downward and that on CD is UPWARD by the Fleming's Left Hand RULE. Hence , AB moves downward and CD upward. These forces are equal in magnitude and opposite in direction, Therefore, As observed from the side AD , the loop ABCD and the axle start rotating in anticlockwise direction. After half rotation, X and Y come in contact with brushes F and E respectively and the current flows in direction E-D-C-B-A-F. Hence, the force on CD is downward and that on AB is upward.Therefore , the loop and the axle continue to rotate in the anticlockwise dierection. After every half rotation, the current in the loop is reversed and the loop and the axle start rotating in the anticlockwise direction. When the current is switched off, the loop stops rotating after some time.

Discussion

16.	a block of mass m is kept on the smooth incline of a wedge of mass M which is place on a smooth frictional horizontal surface find the minimum force F such that the block leave the surface of incline
Answer» PLEASE FIND the ANSWER as ATTACHMENT.

Discussion

17.	Explain why an Electromagnet is called temporary magnet
Answer» Because when electric current removed or can SAY when electric field removed then ELECTROMAGNET LOOSE it's magnetic ABILITY... that's why we called it temporary magnet.

Discussion

18.	9. a race scooter is seen accelerating uniformly from 18.5 m/s to 46.1 m/s in 2.47 seconds. determine the acceleration of the scooter and the distance travelled.
Answer» HEY MATE I HOPE it helps ..(there are so many decimal calculations and I HATE decimal calculations)....

Discussion

19.	A body starts from rest and is uniformly accelerated for 30 sec . the distance travelled in the first 10 sec is x1 next is x2 and last 10 sec is x3 . then the ratio of x1 : x2 : x3 will be ........?
Answer» The RATIOS of DISTANCE TRAVELLED is 1:3:5

Discussion

20.	Question 8.10: In a plane electromagnetic wave, the electric field oscillates sinusoidally at a frequency of 2.0 × 10 10 Hz and amplitude 48 V m −1 . (a) What is the wavelength of the wave? (b) What is the amplitude of the oscillating magnetic field? (c) Show that the average energy density of the E field equals the average energy density of the B field. [c = 3 × 10 8 m s −1 .]Class 12 - Physics - Electromagnetic Waves Electromagnetic Waves Page-286
Answer» (a) wavelength of electromagnetic WAVE is $\lambda=\frac{c}{\nu}$ here, c is speed of light .e.g.,c = 3 × 10^8 m/s v is the frequency .e.g., v = 2 × 10^10 Hz so, $\lambda$ =3 × 10^8/2 × 10^10 = 1.5 × 10^-2 m = 1.5 cm (b) AMPLITUDE of magnetic field is given by $c=\frac{E_0}{B_0}\\B_0=\frac{E_0}{c}=\frac{48Vm^{-1}}{3\times10^8m/s}\\B_0=1.6\times10^{-8}T$ (c) Energy DENSITY as electric field, $U_E=\frac{1}{2}\epsilon_0 E^2$ here, $\frac{E}{B}=c$ so, $U_E=\frac{1}{2}\epsilon_0c^2B^2$ ALSO we know, speed of electromagnetic wave, $c=\frac{1}{\sqrt{\mu_0\epsilon_0}}$ so, $U_E=\frac{1}{2}\frac{\epsilon_0}{\mu_0\epsilon_0}B^2=\frac{B^2}{2\mu_0}=U_B$ here, $U_B$ is energy density as magnetic field.

Discussion

21.	Question 6.3: A long solenoid with 15 turns per cm has a small loop of area 2.0 cm 2 placed inside the solenoid normal to its axis. If the current carried by the solenoid changes steadily from 2.0 A to 4.0 A in 0.1 s, what is the induced emf in the loop while the current is changing?Class 12 - Physics - Electromagnetic Induction Electromagnetic Induction Page-230
Answer» Number of turns on the solenoid = 15 turns/cm = 1500 turns/m so, number of turns per unit length, N = 1500 the solenoid has a small loop of area , A = 2 cm² = 2 × 10^-4 cm² CURRENT carries by the solenoid change from 2A to 4A . so, change in current in the solenoid , ∆i = 4 - 2 = 2A change in time , ∆t = 0.1 s now, induced emf , $e=\frac{d\phi}{dt}$ where $\phi$ is the induced flix through the small loop , e.g., BA [ flux = magnetic field× area] so, $e=\frac{d}{dt}(BA)$ for solenoid B = $\mu_0 ni$ so, $e=\mu_0 nA\frac{di}{dt}$ = 4π × 10^-7 × 1500 × 2 × 10^-4 × (2/0.1) = 7.54 × 10^-6 V HENCE, the induced VOLTAGE in the loop is 7.54 × 10^-6V

Discussion

22.	Compare the power used in 2 ohm resistors in each of the following in of the following circuits1. a 6 volt battery in series with 1 ohm 2 ohm resistor 2. A 4 volt battery in parallel with 12 ohm and 2 ohm resistor
Answer» R= 2 ohm p.d = 6v $p = {v}^{2} \div r \\ p = {6 }^{2} \div 2 \\ p = 36 \div 2 \\ p = 18w$ now for the SECOND ONE

Discussion

23.	When forces F1 , F2 and F3 are acting on a particle of mass m such that F2 and F3 are mutually perpendicular ,then the particle remains stationary . If the force F1 is now removed then the acceleration of the particle is---
Answer» The particle remains STATIONARY on the application of three forces that means the RESULTANT FORCE is 0. This implies F1 = - (F2 + F3) Since, if the force F1 is removed, the forces ACTING are F2 and F3, the resultant of which has the magnitude of F1. Therefore, the acceleration of the particle is F1/m Hope it HELPS u.

23.

When forces F1 , F2 and F3 are acting on a particle of mass m such that F2 and F3 are mutually perpendicular ,then the particle remains stationary . If the force F1 is now removed then the acceleration of the particle is---

Answer»

The particle remains STATIONARY on the application of three forces that means the RESULTANT FORCE is 0.

This implies

F1 = - (F2 + F3)

Since, if the force F1 is removed, the forces ACTING are F2 and F3, the resultant of which has the magnitude of F1.

Therefore, the acceleration of the particle is F1/m

Hope it HELPS u.

Discussion

24.	Name the fuse wire is placed in series with the device
Answer» Fuse is a short LENGTH of wire having LOW melting POINT. It is connected in series with the component to protect it from HIGH current. In CASE of high current,it blows i.e. open the entire circuit.

Discussion

25.	A body is rotating uniformly about a vertical axis fixed in an inertial frame. The resultant force on a particle of the body not on the axis is(a) vertical (b) horizontal and skew with the axis(c) horizontal and intersecting the axis(d) none of these.
Answer» Answer ⇒ Option (C). Horizontal and intersecting the axis. Explanation ⇒ According to the QUESTION, the body is rotating UNIFORMLY, THEREFORE, the particle which is not on the axis will be moving in a uniform circular motion. This circle will be horizontal with its center at the intersecting point with the axis. ∴ It will be having the radial ACCELERATION and hence a radial resultant force. Thus this force will be horizontal and intersecting the axis. *Hence, Option (c). ''Horizontal and intersecting the axis is correct''.* *Hope it helps.*

25.

A body is rotating uniformly about a vertical axis fixed in an inertial frame. The resultant force on a particle of the body not on the axis is(a) vertical (b) horizontal and skew with the axis(c) horizontal and intersecting the axis(d) none of these.

Answer»

Answer ⇒ Option (C). Horizontal and intersecting the axis.

Explanation ⇒ According to the QUESTION, the body is rotating UNIFORMLY, THEREFORE, the particle which is not on the axis will be moving in a uniform circular motion.

This circle will be horizontal with its center at the intersecting point with the axis.

∴ It will be having the radial ACCELERATION and hence a radial resultant force.

Thus this force will be horizontal and intersecting the axis.

Hence, Option (c). ''Horizontal and intersecting the axis is correct''.

Hope it helps.

Discussion

26.	An electric heater of power 3kw is used for 10h. How much energy does it consumes? Express your answer in kWh and joule
Answer» Energy=3kw×10h=30kwh,energy=30×3.6×10^6=1.08×10^8

Discussion

27.	Find the pressure at a depth of 10m in water if the atmospheric pressure is 100kPa. [1Pa=1N/m²] [100kPa=105Pa=105N/m²=1 atm.] [Ans: 198 kPa]
Answer» Given CONDITIONS ⇒ Depth (d)= 10 m. Atmospheric Pressure = 100 kPa = 100 × 10³ Pa. Acceleration due to gravity = 9.8 m/s². Density of the water = 1000 kg/m³. Using the Formula, Pressure = dρg = 10 × 1000 × 9.8 = 98000 Pa. = 98 × 10³ Pa. Total Pressure at the depth of 10 m. = Atmospheric Pressure + Pressure calculated. = 100 × 10³ + 98 × 10³ = 10³(100 + 98) = 198 × 10³ Pa. = 198 kPa. [∵ 10³ = 1 K] Hence, the Pressure at the depth of 10 m is 198 kPa. Hope it HELPS.

27.

Find the pressure at a depth of 10m in water if the atmospheric pressure is 100kPa. [1Pa=1N/m²] [100kPa=105Pa=105N/m²=1 atm.] [Ans: 198 kPa]

Answer»

Given CONDITIONS ⇒

Depth (d)= 10 m.

Atmospheric Pressure = 100 kPa = 100 × 10³ Pa.

Acceleration due to gravity = 9.8 m/s².

Density of the water = 1000 kg/m³.

Using the Formula,

Pressure = dρg

= 10 × 1000 × 9.8

= 98000 Pa.

= 98 × 10³ Pa.

Total Pressure at the depth of 10 m. = Atmospheric Pressure + Pressure calculated.

= 100 × 10³ + 98 × 10³

= 10³(100 + 98)

= 198 × 10³ Pa.

= 198 kPa. [∵ 10³ = 1 K]

Hence, the Pressure at the depth of 10 m is 198 kPa.

Hope it HELPS.

Discussion

28.	Why newtons rings are circular and air wedge is straight?
Answer» NEWTON RINGS have SHAPE known as circular shape. WEDGE is straight

Discussion

29.	If an object is dropped from the top of a building and it reaches the ground at t=4s, then the height of the building is ( ignoring air resistance) (g= 9.8 ms-2)
Answer» T= √(2h/g) 4^2=2h/g h=78.4 I HOPE it HELPS

Discussion

30.	Two identical wires one of Nichrome and other copper are connected in series and a current I is passed through them.State the change observed in the temperature of the 2 wires .Justify your answer .State the law which explains the above observation.Hepl Plzz....
Answer» We know that RESISTANCE is directly proportional to the temperature.since nichrome is an ALLOY so it has more resistance HENCE , it gets more heated.that is why we use nichrome wire in heater for producing more heat to COOK food.we know that alloy has more resistance than a metal. so nichrome has more heat produced capacity than copper wire.so copper has LESS temperature than nicrome. ..........please mark me brainliest ................thank you...................

Discussion

31.	A MAN TRAVELS ONE THIRD LENGTH OF A STRAIGHT ROAD WITH A CONSTANT SPEED OF 40M/S .AND THE REMAINING PORTION OF THE ROAD WITH A CONSTANT SPEED OF 60M/S.THEN CALCULATE ITS AVERAGE SPEED.
Answer» Let TOTAL DISTANCE = x s1= 40m/s. D1= x/3. t1= $\frac{x}{3 \times 40}$ S2 = 60m/s. D2= 2x/3. t2= $\frac{2x}{3 \times 60}$ $average \: <klux>SPEED</klux> = total \: distance \: travelled \div total \: time$ avg. speed= x/3x+4x/360 avg. speed = 360/7= 51.4

Discussion

32.	Give one example to show that friction due to air is much smaller than friction due to liquid
Answer» As we move our HANDS through air we can easily do so. But doing this same process in water is QUITE TOUGH for us to do. PLZ MARK IT AS BRAINLIEST ANSWER. AND DROP A ♥.

Discussion

33.	Which of the following statements about the current in given circuit is correct?
Answer» Heya..!!!! Good AFTERNOON _ Here Is Your ANSWER _ The correct statement about the current in the GIVEN circuit is :- (C) . P has maximum current . Because there is no division of current of P. HOPE YOU UNDERSTAND THE ANSWER ☺️☺️☺️☺️

Discussion

34.	Kinetic energy of body of mass 2kg is 25j its speed is
Answer» 5m/s is the ANSWER FOLLOW me MARK as a BRAINLIST

34.

Kinetic energy of body of mass 2kg is 25j its speed is

Answer»

5m/s is the ANSWER

FOLLOW me

MARK as a BRAINLIST

Discussion

35.	You must have noticed a large mirror at blind driveways, turns and intersections or in parking garage entrances and exits.
Answer» Explanation: General RULES Keep Left on a two-way road to allow traffic from the opposite direction to pass on your right and on a ONE-way road to allow vehicles behind you to overtake from your right. When Turning Left keep to the left side of the road you are leaving as well as the one you are entering. When turning right, move to the centre of the road you are leaving and arrive near the left side of road you are entering. Slow Down at road junctions, INTERSECTIONS, pedestrian crossings and road corners and wait until you are SURE of a clear passage ahead. if you are entering a main road where traffic is not being regulated, give way to vehicles passing on your right.

35.

You must have noticed a large mirror at blind driveways, turns and intersections or in parking garage entrances and exits.

Answer»

Explanation:

General RULES Keep Left on a two-way road to allow traffic from the opposite direction to pass on your right and on a ONE-way road to allow vehicles behind you to overtake from your right.

When Turning Left keep to the left side of the road you are leaving as well as the one you are entering. When turning right, move to the centre of the road you are leaving and arrive near the left side of road you are entering.

Slow Down at road junctions, INTERSECTIONS, pedestrian crossings and road corners and wait until you are SURE of a clear passage ahead. if you are entering a main road where traffic is not being regulated, give way to vehicles passing on your right.

Discussion

36.	Certain force acting on a 20 kg mass changes its velocity from 5 m/s to 2 m/s.. calculate the work done by the force
Answer» Answer: The work done by the force is –210 JOULE. ____________________________ Explanation: Given: Mass (m) = 20 kg. Initial VELOCITY (u) = 5 m/s. Final velocity (v) = 2 m/s. _________________________ To FIND: We have to find the work done by the force. _________________ Solution: We know that, Work done = Force × distance ⇒ W = F × s [Since F = ma and s = (v²– u²/2a)] ⇒W = ma{v²– u²/2a} = 20a{(2²– 5²/2a)} = 20{(4-25/2)} = 10 × –21 = –210 Joule. ___________________________________ Thus, –210 Joule is the required answer.

36.

Certain force acting on a 20 kg mass changes its velocity from 5 m/s to 2 m/s.. calculate the work done by the force

Answer»

Answer:

The work done by the force is –210 JOULE.

____________________________

Explanation:

Given:

Mass (m) = 20 kg.
Initial VELOCITY (u) = 5 m/s.
Final velocity (v) = 2 m/s.

_________________________

To FIND:

We have to find the work done by the force.

_________________

Solution:

We know that,

Work done = Force × distance

⇒ W = F × s

[Since F = ma and s = (v²– u²/2a)]

⇒W = ma{v²– u²/2a}

= 20*a*{(2²– 5²/2a)}

= 20{(4-25/2)}

= 10 × –21 = –210 Joule.

___________________________________

Thus, –210 Joule is the required answer.

Discussion

37.	A) for the circuit shown in figure belowo, calethe current I and voltage vab when i Rx = 0;) R₂ = 15kohm iii) Rx =infinite
Answer» Answer: Wall wo wo sites aaj at all so epic all so will AVOID AKTA

37.

A) for the circuit shown in figure belowo, calethe current I and voltage vab when i Rx = 0;) R₂ = 15kohm iii) Rx =infinite

Answer»

Answer:

Wall wo wo sites aaj at all so epic all so will AVOID AKTA

Discussion

38.	Write the main function of food
Answer» ANSWER: This is a PHOTO EXPLANATION: HOPE YOU LIKE IT

38.

Write the main function of food

Answer»

ANSWER:

This is a PHOTO

EXPLANATION:

HOPE YOU LIKE IT

Discussion

39.	What is thermodynamics in physics
Answer» EXPLANATION: Thermodynamics, science of the relationship between HEAT, work, temperature, and energy. In broad terms, thermodynamics DEALS with the transfer of energy from one place to another and from one form to another. The key CONCEPT is that heat is a form of energy corresponding to a definite amount of mechanical work. HOPE IT HELPS U BUDDY

39.

What is thermodynamics in physics

Answer»

EXPLANATION:

Thermodynamics, science of the relationship between HEAT, work, temperature, and energy. In broad terms, thermodynamics DEALS with the transfer of energy from one place to another and from one form to another. The key CONCEPT is that heat is a form of energy corresponding to a definite amount of mechanical work.

HOPE IT HELPS U BUDDY

Discussion

40.	State and explain laws of conservation of mechanical energy?
Answer» Explanation: hi The principle of the conservation of MECHANICAL energy states that the total mechanical energy in a system (i.e., the sum of the potential plus KINETIC ENERGIES) remains constant as long as the only forces ACTING are conservative forces. M#

40.

State and explain laws of conservation of mechanical energy?

Answer»

Explanation:

hi

The principle of the conservation of MECHANICAL energy states that the total mechanical energy in a system (i.e., the sum of the potential plus KINETIC ENERGIES) remains constant as long as the only forces ACTING are conservative forces.

M#

Discussion

41.	A concave spherical mirror forms a 40cm high real image of an object whose height is 10cm. Theradius of the mirror is 60cm. Find the distance from the object to its image.1)90cm2)112.5cm3)97.5cm4)75cm
Answer» ANSWER: 2)112.5 *<U>I'm* *SURE* *about* *this* *answer* u *can* *BELIEVE* *this.*....

41.

A concave spherical mirror forms a 40cm high real image of an object whose height is 10cm. Theradius of the mirror is 60cm. Find the distance from the object to its image.1)90cm2)112.5cm3)97.5cm4)75cm

Answer»

ANSWER:

2)112.5

<U>I'm SURE about this answer u can BELIEVE this.....

Discussion

42.	Find I in the circuit
Answer» ANSWER: BRAIN LIST MEEEE.......

42.

Find I in the circuit

Answer»

ANSWER:

BRAIN LIST MEEEE.......

Discussion

43.	Firatt law of thermodynamic states that
Answer» Answer: ENERGY exists in MANY forms, such as heat, light, chemical energy, and electrical energy. ... The First LAW of THERMODYNAMICS (Conservation) states that energy is always conserved, it cannot be created or destroyed. In ESSENCE, energy can be converted from one form into another. Explanation: please mark me as brainliest

43.

Firatt law of thermodynamic states that

Answer»

Answer:

ENERGY exists in MANY forms, such as heat, light, chemical energy, and electrical energy. ... The First LAW of THERMODYNAMICS (Conservation) states that energy is always conserved, it cannot be created or destroyed. In ESSENCE, energy can be converted from one form into another.

Explanation:

please mark me as brainliest

Discussion

44.	WHAT IS NOUN? HELP ME ANYONE HE FRAUD ME GIRLS HELP ME PLEASE PLEASE CHECK MY BIO
Answer» ANSWER: I HOPE this is HELPFUL to you FRIEND

44.

WHAT IS NOUN? HELP ME ANYONE HE FRAUD ME GIRLS HELP ME PLEASE PLEASE CHECK MY BIO

Answer»

ANSWER:

I HOPE this is HELPFUL to you FRIEND

Discussion

45.	Find unit vector which is perpendicular to both 3I+4j and 4j_5k
Answer» ANSWER: MARK me BRAINLIST PLZ i will GIVE you lol Explanation:

45.

Find unit vector which is perpendicular to both 3I+4j and 4j_5k

Answer»

ANSWER:

MARK me BRAINLIST PLZ i will GIVE you lol

Explanation:

Discussion

46.	When a wheel turns through an angle of 180° it lays out a tangential distanceequal to:(Pus(a) pier(c) 2r(d) piersquare
Answer» Question When a wheel turns through an ANGLE of 180° it LAYS out a tangential distance Answer (a) pier

46.

When a wheel turns through an angle of 180° it lays out a tangential distanceequal to:(Pus(a) pier(c) 2r(d) piersquare

Answer»

Question

When a wheel turns through an ANGLE of 180° it LAYS out a tangential distance

Answer

(a) pier

Discussion

47.	Tell me fast friends.
Answer» EXPLANATION: I hope this helps you good MORNING have a NICE DAY

47.

Tell me fast friends.

Answer»

EXPLANATION:

I hope this helps you

good MORNING

have a NICE DAY

Discussion

48.	If increase in linear momentum of a body is 50% the change in its kinetic energy
Answer» Answer: 125% EXPLANATION: HOPE this helps U....... please mark as BRAINLIST......

48.

If increase in linear momentum of a body is 50% the change in its kinetic energy

Answer»

Answer:

125%

EXPLANATION:

HOPE this helps U.......

please mark as BRAINLIST......

Discussion

49.	24. Give three points of differences between speed and velocity.
Answer» ANSWER: Speed and velocity Explanation: speed 1, speed is scalar quantity 2, speed = Distance / TIME 3,speed of body is always ZERO and positive Velocity 1, velocity is vector quantity 2, velocity = Displacement / time 3, Velocity of a body is always NEGATIVE or zero

49.

24. Give three points of differences between speed and velocity.

Answer»

ANSWER:

Speed and velocity

Explanation:

speed

1, speed is scalar quantity

2, speed = Distance / TIME

3,speed of body is always ZERO and positive

Velocity

1, velocity is vector quantity

2, velocity = Displacement / time

3, Velocity of a body is always NEGATIVE or zero

Discussion

50.	Define specific resistance of material
Answer» ANSWER: Specific RESISTANCE (”ρ”) is a property of any conductive material, a FIGURE used to DETERMINE the end-to-end resistance of a conductor given length and area in this FORMULA: R = ρl/A.

50.

Define specific resistance of material

Answer»

ANSWER:

Specific RESISTANCE (”ρ”) is a property of any conductive material, a FIGURE used to DETERMINE the end-to-end resistance of a conductor given length and area in this FORMULA: R = ρl/A.

Discussion

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Answer:

Explanation:

Given:

To FIND:

Solution:

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ANSWER:

This is a PHOTO

EXPLANATION:

HOPE YOU LIKE IT

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<U>I'm SURE about this answer u can BELIEVE this.....

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WHAT IS NOUN? HELP ME ANYONE HE FRAUD ME GIRLS HELP ME PLEASE PLEASE CHECK MY BIO ​​

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Question

Answer

Tell me fast friends.​

If increase in linear momentum of a body is 50% the change in its kinetic energy​

125%

HOPE this helps U.......

please mark as BRAINLIST......

24. Give three points of differences between speed and velocity.​

Define specific resistance of material ​

Kinetic energy of body of mass 2kg is 25j its speed is

You must have noticed a large mirror at blind driveways, turns and intersections or in parking garage entrances and exits.

Certain force acting on a 20 kg mass changes its velocity from 5 m/s to 2 m/s.. calculate the work done by the force

A) for the circuit shown in figure belowo, calethe current I and voltage vab when i Rx = 0;) R₂ = 15kohm iii) Rx =infinite

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What is thermodynamics in physics

State and explain laws of conservation of mechanical energy?

A concave spherical mirror forms a 40cm high real image of an object whose height is 10cm. Theradius of the mirror is 60cm. Find the distance from the object to its image.1)90cm2)112.5cm3)97.5cm4)75cm

Find I in the circuit

Firatt law of thermodynamic states that

WHAT IS NOUN? HELP ME ANYONE HE FRAUD ME GIRLS HELP ME PLEASE PLEASE CHECK MY BIO

Find unit vector which is perpendicular to both 3I+4j and 4j_5k

When a wheel turns through an angle of 180° it lays out a tangential distanceequal to:(Pus(a) pier(c) 2r(d) piersquare

Tell me fast friends.

If increase in linear momentum of a body is 50% the change in its kinetic energy

24. Give three points of differences between speed and velocity.

Define specific resistance of material