Download The three toed sloth is the slowest moving land mamal on the

MECHANICS
UNIFORM ACCELERATED MOTION
1) The three toed sloth is the slowest moving land mammal on the
ground, it moves with a velocity of 0.037 ms-1 , considerably slower
than the giant tortoise which walks at 0.076 ms-1. If they both set off
at the same time what is their separation after 12 mins of walking ?
2) A particle has a initial velocity of + 112 ms-1 at t = 0, it has no
acceleration until t = 3s and from then on it has an acceleration of -4
ms-1. What is its velocity at t = 16s ?
3) The length of a barrel of a primitive blow gun is 1.2m. Upon
leaving the barrel the dart has a speed of 14 ms-1. If the acceleration is
constant how long does it take the dart to travel the length of the
barrel ?
4) Suppose a car is travelling at 12 ms-1 and the driver sees a red light.
After 0.510s (his reaction time) he depresses the brakes and the car
decelerates at 6.2 ms-2. What is the total stopping distance of the car ?
5) A golf ball is dropped and rebounds off the ground with a velocity
of
5 ms-1 to what height does the ball rise to ?
6) How long does it take until the between this bounce and the next ?
7) At what initial velocity must an arrow be fired straight up to attain
a height of 110m in 5.4s ?
IMPULSE & MOMENTUM
8) What is the impulse of a 35N force that acts on an object for 0.4s?
9) A woman drives a golf ball (mass = 0.045kg) with an initial
velocity of 28 ms-1. The impact is of duration 6 * 10-3 s.
a) What is the change in momentum ?
b) What is the average force applied to the ball ?
10) A 55kg swimmer is standing on a stationary 210kg floating raft.
The swimmer runs off the raft with a velocity of +4.6 ms-1, what is the
recoil velocity of the raft ?
11) An astronaut is motionless in outer space and upon a command
the propulsion unit on his back ejects some gas with a velocity of +14
ms-1. The astronaut (mass 160kg) recoils with a velocity of -0.5 ms-1.
What was the mass of the gas ?
12) A two stage rocket moves in space with a constant velocity of
4900 ms-1. The two stages then are separated by a small explosion and
the 1200kg upper stage moves off at 5700 ms-1 in the same direction.
What is the velocity of the 2400kg lower stage after the explosion ?
13) In a game of American football a receiver is standing still, having
just caught the ball, before he can move a tackler running at +4.5 ms-1
grabs him and the two move off together with a velocity of +2.6 ms-1.
If the mass of the tackler is 115kg what is the mass of the receiver ?
14) In movies Superman hovers stationary in mid-air, grabs a villain
by the throat and throws him backwards whilst he remains stationary.
Using the law of conservation of linear momentum, explain what is
wrong with this situation.