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| 1. |
Cricket ball of mass 150 g moving at speed of 30 m/s is brought to rest by player in 0.03 find force |
| Answer» MASS of the ball (m) =150 g or 0.15 kg initial velocity (u) =30 m/s time (t) = 0.03 sec. final velocity (v) = 0 Initial MOMENTUM = mu = 0.15 kg * 30 m/s = 4.5 kg m/s Final momentum = mv (which is equal to 0, since v is zero) Change in momentum = mv-mu = 0 - 4.5 = -4.5 kg m/s Average force = Change in momentum / time = -4.5 kg ms^-1 /0.03 s = -150 kg m/s^2 = -150 N The negative sign ACTUALLY shows that the force was applied opposite to the direction of the motion of the ball. So, the average force applied by the PLAYER will be 150 N. | |