KINEMATICS IMPORTANT NUMERICALS FOR JEE/NEET

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Ques 1. On turning a corner a motorist rushing and 44 m/s finds a child on the road ahead. He instantly stops the engine and applies the brakes so as to stop it will in one metre of the child calculate time required to stop it.

Ans. 4.5 sec
 
Ques 2. An object is thrown vertically upwards with some speed. It crosses two points p, q which are separated by h metre. If TP is the time between p and highest point and coming back at t q is the time between q and highest point and coming back, relate acceleration due to gravity, 
t p, t q and h. 

Ans. g =8h/(t p²-t q²) 

Ques 3. A body covers 12 metre in 2 seconds and 20 metre in 4 second. Find what distance the body will cover in 4 seconds after 5 th second. 

Ans. 136 metre

Ques 4. Two bodies are released from the same height at an interval of 1 second. How long after the first body begins to fall will the two bodies be 10 metre apart?

Ans. 1.5 second

Ques 5. A particle experiences constant acceleration for 20 seconds after starting from rest. If it travels a distance S1 in first 10 seconds and distance S2 to in the next 10 seconds, find the relation between S1 and S2. 

Ans. S2 = 3 S1

Ques 6. A ball is dropped from the roof of a tower of height h. The total distance covered by it in the last second of its motion is equal to the distance covered by it in the first three second. What is the value of h? 

Ans. 125 metre

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