Advertisements
Advertisements
प्रश्न
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.
Advertisements
उत्तर
Given, the mass of the body (m) = 2 kg
From the position-time graph, the body is at x = 0 when t = 0, i.e., body is at rest.
∴ Impulse at t = 0, s = 0, is zero
From t =0 s to t = 4 s, the position-time graph is a straight line, which shows that body moves with uniform velocity.
Beyond t = 4 s, the graph is a straight line parallel to time ads, i.e., the body is at rest (v = 0).
The velocity of the body = slope of a position-time graph
= tan θ = `3/4` m/s
impulse (at t = 4 s) = change in momentum
= mv – mu
= m(v – u)
= `2(0 - 3/4)`
= `- 3/2` kg-m/s = – 1.5 kg-m/s
APPEARS IN
संबंधित प्रश्न
Two bodies of masses 10 kg and 20 kg respectively kept on a smooth, horizontal surface are tied to the ends of a light string. A horizontal force F = 600 N is applied to
- A,
- B along the direction of string. What is the tension in the string in each case?
Suppose you are running fast in a field and suddenly find a snake in front of you. You stop quickly. Which force is responsible for your deceleration?
Two objects A and B are thrown upward simultaneously with the same speed. The mass of A is greater than that of B. Suppose the air exerts a constant and equal force of resistance on the two bodies.
If the tension in the cable supporting an elevator is equal to the weight of the elevator, the elevator may be
(a) going up with increasing speed
(b) going down with increasing speed
(c) going up with uniform speed
(d) going down with uniform speed
A block of mass 0.2 kg is suspended from the ceiling by a light string. A second block of mass 0.3 kg is suspended from the first block by another string. Find the tensions in the two strings. Take g = 10 m/s2.
Find the reading of the spring balance shown in the following figure. The elevator is going up with an acceleration g/10, the pulley and the string are light and the pulley is smooth.
Consider the situation shown in the following figure. Both the pulleys and the string are light and all the surfaces are frictionless.
- Find the acceleration of the mass M.
- Find the tension in the string.
- Calculate the force exerted by the clamp on the pulley A in the figure.
Find the acceleration of the blocks A and B in the three situations shown in the following figure.
The monkey B, shown in the following figure, is holding on to the tail of monkey A that is climbing up a rope. The masses of monkeys A and B are 5 kg and 2 kg, respectively. If A can tolerate a tension of 30 N in its tail, what force should it apply on the rope in order to carry monkey B with it? Take g = 10 m/s2.
An aeroplane is moving uniformly at a constant height under the action of two forces (i) Upward force (lift) and (ii) Downward force (weight). What is the net force on the aeroplane?
A tennis ball and a cricket ball , both are stationary. To start motion in them .
Show that the rate of change of momentum = mass × acceleration. Under what condition does this relation hold?
The linear momentum of a ball of mass 50 g is 0.5 kg m s-1. Find its velocity.
A body of mass 200 g is moving with a velocity of 5 ms−1. If the velocity of the body changes to 17 ms−1, calculate the change in linear momentum of the body.
Define Newton’s second law of motion.
Name the physical entity used for quantifying the motion of a body.
Why is it advantageous to turn before taking a long jump?
A stone is dropped from a cliff 98 m high.
How long will it take to fall to the foot of the cliff?
Why does a child feel more pain when she falls down on a hard cement floor, than when she falls on the soft muddy ground in the garden?
