A man drops a ball downside from the roof of a tower of height 400 m.

1.	A man drops a ball downside from the roof of a tower of height 400 m. At the same time another ball is thrown upside with a velocity 50m/s, from the surface bottom. Then they will meet at which height from the surface of the tower.A. 100 mB. 320 mC. 80 mD. 240 m
Answer» A ball dropped from the roof of height 400m. Let after t time it meets with another ball . displacement covered by ball during this time ( S₁ ) = ut + 1/2at² = 0× t + 1/2 × 10 × t² = 5t² another ball is thrown from the surface of tower with speed 50m/sec . then, displacement covered by another ball (S₂) = ut +1/2at² = 50t - 1/2× 10t² =50t -5t² for collision, S₁ + S₂ = 400 5t² + 50t - 5t² = 400 50t = 400 t = 8sec hence, body collide in 8sec. then, displacement covered by first body during this time= 5 × 64 = 320m collision occurs 80m height from the surface of tower .

A man drops a ball downside from the roof of a tower of height 400 m. At the same time another ball is thrown upside with a velocity 50m/s, from the surface bottom. Then they will meet at which height from the surface of the tower.A. 100 mB. 320 mC. 80 mD. 240 m

Answer»

A ball dropped from the roof of height 400m.

Let after t time it meets with another ball .
displacement covered by ball during this time ( S₁ ) = ut + 1/2at²
= 0× t + 1/2 × 10 × t²
= 5t²

another ball is thrown from the surface of tower with speed 50m/sec .
then, displacement covered by another ball (S₂) = ut +1/2at²
= 50t - 1/2× 10t²
=50t -5t²

for collision,
S₁ + S₂ = 400
5t² + 50t - 5t² = 400
50t = 400
t = 8sec

hence, body collide in 8sec.

then, displacement covered by first body during this time= 5 × 64 = 320m

collision occurs 80m height from the surface of tower .

Discussion

No Comment Found

Related InterviewSolutions

What is the difference between multimolecular and macromolecular collids ? Give one example of each . How are associated colloids different from these two types of colloids ?
Gastrointestinal irritation, cardiovascular effects, including tachycardia,arrhythmias, and orthostatic hypotension, mental disturbances, and withdrawalare possible adverse effects of: A. Amantadine B. Benztropine C. Levodopa D. selegiline
Match the column I and IIColumn-IColumn-II(a)Parasitism(i)++(b)Commensalism(ii)+ –(c)Amensalism(iii)0 + (d)Mutualism(iv)0 –(1) (a) - iii, (b) - ii, (c) - iv, (d) - i (2) (a) - i, (b) - ii, (c) - iii, (d) - iv (3) (a) - ii, (b) - iii, (c) - i, (d) - iv (4) (a) - ii, (b) - iii, (c) - iv, (d) - i
Assertion: In commensalism, one organism is benefitted and other is unaffected Reason: Cattle egret bird and cattle is an example of commensalism (1) If both assertion and reason are true and reason is the correct explanation of assertion. (2) If both assertion and reason are true but reason is not the correct explanation of assertion. (3) If assertion is true but reason is false. (4) If both assertion and reason are false.
In charge of Calcutta Mint between 1832 to 1838, he studied and deciphered Ashokan rocks and pillars. His essays on antiquities are considered as classics. Hint: Varanasi. Who are we referring to?
Nature of climax community depends upon(A) Climate (B) Water (C) Soil fertility (D) Temperature
How do biofertilisers enrich the fertility of the soil?
Read carefully the passage and select the correct answer out of given four options:Biofertilizers are organisms that enrich nutrient quality of the soil. The important sources of biofertilizers are bacteria, fungi and cyanobacteria. The symbiotic association of Rhizobium with the root nodules of leguminous plants is the common example. These bacteria convert atmospheric nitrogen into nitrogenous compound and fix in the soil.The organisms which enrich the nutrient quality of the soil are called(a) Microbes(b) Biofertilizers(c) Yeast(d) Biopesticides
Electrophoresis is an essential procedure that needs to be employed in genetic fingerprinting why?
Assertion: Angiosperms form endosperm after fertilization and is diploid. Reason: In gymnosperms, endosperm is formed before fertilization and is triploid. a. Both assertion and reason are true, and reason is the correct explanation of assertion. b. Both assertion and reason are true, but reason is not the correct explanation of assertion. c. Assertion is true but reason is false. d. Both assertion and reason are false.