Advertisements
Advertisements
Question
A woman throws an object of mass 500 g with a speed of 25 ms1.
- What is the impulse imparted to the object?
- If the object hits a wall and rebounds with half the original speed, what is the change in momentum of the object?
Advertisements
Solution
Mass of the object (m) = 500 g = 0.5 kg
Speed of the object (v) = 25 m/s
a. Impulse imparted to the object = Change in momentum
= mv – mu
= m(v – u)
= 0.5(25 – 0)
= 12.5 N-s
b. Velocity of the object after rebounds
= `- 25/2` m/s
v' = – 12.5 m/s
∴ Change in momentum = m(v’ – v)
= 0.5 (– 12.5 – 25)
= – 18.75 N-s
APPEARS IN
RELATED QUESTIONS
A monkey of mass 40 kg climbs on a rope in given Figure which can stand a maximum tension of 600 N. In which of the following cases will the rope break: the monkey
(a) climbs up with an acceleration of 6 m s–2
(b) climbs down with an acceleration of 4 m s–2
(c) climbs up with a uniform speed of 5 m s–1
(d) falls down the rope nearly freely under gravity?
(Ignore the mass of the rope).
An object is placed far away from all the objects that can exert force on it. A frame of reference is constructed by taking the origin and axes fixed in this object. Will the frame be necessarily inertial?
The force of buoyancy exerted by the atmosphere on a balloon is B in the upward direction and remains constant. The force of air resistance on the balloon acts opposite the direction of velocity and is proportional to it. The balloon carries a mass M and is found to fall to the earth's surface with a constant velocity v. How much mass should be removed from the balloon so that it may rise with a constant velocity v?
An empty plastic box of mass m is found to accelerate up at the rate of g/6 when placed deep inside water. How much sand should be put inside the box so that it may accelerate down at the rate of g/6?
A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration of 12 m/s2. Find the displacement of the block during the first 0.2 s after the start. Take g = 10 m/s2.
A tennis ball and a cricket ball , both are stationary. To start motion in them .
State Newton's second law of motion. Under what condition does it take the form F = ma?
Calculate the magnitude of force which when applied on a body of mass 0.5 kg produces an acceleration of 5 m s-2.
How long will a stone take to fall to the ground from the top of a building 80 m high
A pebble is dropped freely in a well from its top. It takes 20 s for the pebble to reach the water surface in the well. Taking g = 10 m s-2 and speed of sound = 330 m s-1. Find : The time when echo is heard after the pebble is dropped.
Calculate the velocity of a body of mass 0.5 kg, when it has a linear momentum of 5 Ns.
What do you understand by the term momentum?
State two factors which determine the momentum of a body.
Why is it advantageous to turn before taking a long jump?
A ball is thrown vertically downward with an initial velocity of 10 m/s. What is its speed 1 s later and 2 s later?
A ball is thrown upward and reaches a maximum height of 19.6 m. Find its initial speed?
In the previous problem (5.3), the magnitude of the momentum transferred during the hit is ______.
The position time graph of a body of mass 2 kg is as given in figure. What is the impulse on the body at t = 0 s and t = 4 s.
According to Newton's Second Law of Motion, what quantity is directly proportional to the applied force?
As shown in figure, a 70 kg garden roller is pushed with a force of F = 200 N at an angle of 30° with horizontal. The normal reaction on the roller is: (Given: g = 10 ms−2)
