Advertisements
Advertisements
प्रश्न
A cricket player holds a cricket ball of mass 100 g by moving his hands backward by 0.75 m. If the initial velocity of the ball is 108 kmh−1, find the retarding force applied by the player.
उत्तर
Mass of ball – m = 100 g = 0.1 kg
Distance covered = S = 0.75 m
Initial velocity of ball = u = 108 kmh−1
u = `108xx5/18` ms−1 = 30 ms−1
Final velocity of car = v = 0
Retarding force = F = ?
v2 – w2 = 2a S
(0)2 − (30)2 = 2a (0.75)
1.5 a = −900
a = `-900/1.5` = −600 ms−2
Retarding force = F = ma
F = 0.1 × (−600)
F = −60 N
APPEARS IN
संबंधित प्रश्न
Give one example in each case where :
The force is of contact, and
Force is at a distance
Give one example in each of the following cases where a force:
(i) Stops a moving body.
(ii) Moves a stationary body.
(iii) Changes the size of a body.
(iv) Changes the shape of a body.
Is force needed to keep a moving body in motion?
A ball moving on a table top eventually stops. Explain the reason .
Two equal and opposite forces act on a stationary body. Will the body move? Give a reason to your answer.
A force is needed to :
The CGS unit of force is dyne:
∴1 N = __________ dyne
Gravitational force is a ______ force.
In the circuit shown in figure, when the key is closed, the compass needle placed in the match box deflects. Name the force which cases this deflection.
Does the force of gravity act on dust particles?