body rises vertically upto a height of 125 m in 5 s & then comes back

1.	body rises vertically upto a height of 125 m in 5 s & then comes back to the same point. Find the (i) total distance travelled, (ii) average speed, (iii) displacement and (iv) average velocity of the body.
Answer» Answer : Maximum height attained = 125m Time to reach there = 5S Body comes back to the same point $.$ We have to find Total distance travelled Average speed DISPLACEMENT Average velocity 1) Distance is DEFINED as the total length of actual path which is covered by moving object. It is a scalar quantity. Here body rises to the height of 125m then comes back to the initial position. Therefore distance covered by body will be two times of 125m. ➝ d = 125 × 2 ➝ d = 250 m 2) Average speed is defined as the ratio of total distance travelled to the total time taken. Here body takes 5s to reach at the maximum height. We know that time of ascent is always equal to the time of descent. Therefore total time of flight will be 10s. ➝ Vav = d/t ➝ Vav = 250/10 ➝ Vav = 25 m/s 3) Displacement is defined as the SHORTEST distance between initial and final position of the entire journey. ATQ, body comes back to the initial position therefore displacement will be zero. 4) Average velocity is defined as the ratio of displacement to the total time. Displacement of the body is zero therefore average velocity will also be zero.

body rises vertically upto a height of 125 m in 5 s & then comes back to the same point. Find the (i) total distance travelled, (ii) average speed, (iii) displacement and (iv) average velocity of the body.

Answer»

Maximum height attained = 125m

Time to reach there = 5S

Body comes back to the same point $.$

We have to find

1) Distance is DEFINED as the total length of actual path which is covered by moving object. It is a scalar quantity.

Here body rises to the height of 125m then comes back to the initial position.

Therefore distance covered by body will be two times of 125m.

➝ d = 125 × 2

➝ d = 250 m

2) Average speed is defined as the ratio of total distance travelled to the total time taken.

Here body takes 5s to reach at the maximum height. We know that time of ascent is always equal to the time of descent.

Therefore total time of flight will be 10s.

➝ Vav = d/t

➝ Vav = 250/10

➝ Vav = 25 m/s

3) Displacement is defined as the SHORTEST distance between initial and final position of the entire journey.

ATQ, body comes back to the initial position therefore displacement will be zero.

4) Average velocity is defined as the ratio of displacement to the total time.

Displacement of the body is zero therefore average velocity will also be zero.