Q 1:
Which couldpotentially cause you the greaterinjury; being tackled by alight-weight,
fast-moving footballplayer, or being tackled by aplayer with double the massbut
moving at half thespeed? Marks=5
Q 2:
For each situation,state whether the collision iselastic or inelastic. If it isinelastic, state
whether it iscompletely inelastic or not?
a) You drop a ballfrom your hand. It collides withthe floor and bounces back upso
that it just reachesyour hand.
b) You drop adifferent ball from your hand and letit collide with the ground.This
ball bounces back upto half the height from whichit was dropped.
c) You drop a ball ofclay from your hand. When itcollides with the ground, itstops.
Marks =5
2
Q 3:
Will the centre ofmass in Fig, 1 continue on thesame parabolic trajectory even afterone
of the fragments hitsthe ground? Why or why not?Marks = 5
Fig 1. A shellexplodes into two fragments inflight. If air is ignored, thecentre of mass
continues on the sametrajectory as the shellâs pathbefore exploding.
Q 4:
(a)If a rocket ingravity- free outer space has thesame thrust at all times, isits
acceleration constant,increasing or decreasing?
(b) If the rocket hasthe same acceleration at alltimes, is the thrust constant,increasing or
decreasing?
Q 1:
Which couldpotentially cause you the greaterinjury; being tackled by alight-weight,
fast-moving footballplayer, or being tackled by aplayer with double the massbut
moving at half thespeed? Marks=5
Q 2:
For each situation,state whether the collision iselastic or inelastic. If it isinelastic, state
whether it iscompletely inelastic or not?
a) You drop a ballfrom your hand. It collides withthe floor and bounces back upso
that it just reachesyour hand.
b) You drop adifferent ball from your hand and letit collide with the ground.This
ball bounces back upto half the height from whichit was dropped.
c) You drop a ball ofclay from your hand. When itcollides with the ground, itstops.
Marks =5
2
Q 3:
Will the centre ofmass in Fig, 1 continue on thesame parabolic trajectory even afterone
of the fragments hitsthe ground? Why or why not?Marks = 5
Fig 1. A shellexplodes into two fragments inflight. If air is ignored, thecentre of mass
continues on the sametrajectory as the shellâs pathbefore exploding.
Q 4:
(a)If a rocket ingravity- free outer space has thesame thrust at all times, isits
acceleration constant,increasing or decreasing?
(b) If the rocket hasthe same acceleration at alltimes, is the thrust constant,increasing or
decreasing?
