A 0.145 kg baseball pitched at 33.m/s is hit on a horizontal line drive straight back at the pitcher at 46.0 m/s. If the contact time between bat and ball is 5.70×10−3 s, calculate the magnitude of the force (assumed to be constant) exerted on the ball by the bat.

F = 2009.64 N

Explanation:

It is given that,

Mass of a baseball, m = 0.145 kg

Initial speed if the baseball, u = 33 m/s

It hit on a horizontal line drive straight back at the pitcher at 46.0 m/s, final velocity, v = -46 m/s

Time of contact between the bat and the ball is

We need to find the magnitude of the force exerted by the ball on the bat. It can be calculated using impulse-momentum theorem. So,

So, the magnitude of force exerted on the ball by the bat is 2009.64 N.

b.

explanation:

5 w for 1hr = 5x60x60 joules=300x60=3000x6=18,000j as total energy conversion. efficiency of bulb needed for radiant to thermal within 18000