NEET Kinematics — Set 17

Question 1

A ball is thrown upwards with a speed of $ 44 \, \text{m/s} $. What is the total time of flight? (Take $ g = 10 \, \text{m/s}^2 $)

Accepted Answer

Time to max height: $ v = v_0 + a t $, $ 0 = 44 - 10 t \Rightarrow t = 4.4 \, \text{s} $. Total time = time up + time down = $ 4.4 \, \text{s} + 4.4 \, \text{s} = 8.8 \, \text{s} $. The total time is $ 8.8 \, \text{s} $.

Question 2

A person walks $ 12 \, \text{m} $ in $ 3 \, \text{s} $ and then walks back $ 6 \, \text{m} $ in $ 2 \, \text{s} $. What is the average speed?

Accepted Answer

Average speed = total distance / total time. Total distance = $ 12 \, \text{m} + 6 \, \text{m} = 18 \, \text{m} $, total time = $ 3 \, \text{s} + 2 \, \text{s} = 5 \, \text{s} $. Average speed = $ \frac{18}{5} = 3.6 \, \text{m/s} $.

Question 3

A stone is dropped from rest. What is its velocity after falling $ 24.5 \, \text{m} $? (Take $ g = 10 \, \text{m/s}^2 $)

Accepted Answer

Use $ v^2 = v_0^2 + 2 g y $. Here, $ v_0 = 0 $, $ g = 10 \, \text{m/s}^2 $, $ y = 24.5 \, \text{m} $. Substitute: $ v^2 = 0 + 2 \cdot 10 \cdot 24.5 = 490 \Rightarrow v = \sqrt{490} \approx 22.14 \, \text{m/s} $. Rounded to one decimal, the velocity is $ 22.1 \, \text{m/s} $.

NEET Physics: Kinematics — Practice Set 17

Q1. A ball is thrown upwards with a speed of \( 44 \, \text{m/s} \). What is the total time of flight? (Take \( g = 10 \, \text{m/s}^2 \))

Q2. A person walks \( 12 \, \text{m} \) in \( 3 \, \text{s} \) and then walks back \( 6 \, \text{m} \) in \( 2 \, \text{s} \). What is the average speed?

Q3. A stone is dropped from rest. What is its velocity after falling \( 24.5 \, \text{m} \)? (Take \( g = 10 \, \text{m/s}^2 \))

Q4. A stone falls freely from a height and reaches the ground with a velocity of \( 34.3 \, \text{m/s} \). What is the height? (Take \( g = 9.8 \, \text{m/s}^2 \))

Q5. Two balls are dropped from a height of \( 125 \, \text{m} \), \( 2 \, \text{s} \) apart. How long after the second ball is released do they meet if the first ball rebounds at \( 10 \, \text{m/s} \) upon hitting the ground? (Take \( g = 10 \, \text{m/s}^2 \))

Q6. A car moving at \( 12 \, \text{m/s} \) decelerates uniformly to rest in \( 3 \, \text{s} \). What is the distance covered?

Q7. A truck moving at \( 90 \, \text{km/h} \) applies brakes and stops after \( 12 \, \text{s} \). If the deceleration triples after \( 8 \, \text{s} \), what is the total distance covered?

Q8. A ball is thrown upwards with a speed of \( 26 \, \text{m/s} \). What is its velocity after \( 2 \, \text{s} \)? (Take \( g = 10 \, \text{m/s}^2 \))

Q9. A car accelerates from \( 10 \, \text{m/s} \) at \( 1.5 \, \text{m/s}^2 \) for \( 6 \, \text{s} \), then moves at constant speed for \( 4 \, \text{s} \). What is the average speed over the entire motion?

Q10. An object falls freely from a height. After \( 3 \, \text{s} \), what is the distance covered? (Take \( g = 10 \, \text{m/s}^2 \))