Answer
given,
mass of base ball = 0.14 kg
speed before it made the contact with the ball (V i) = 42 m/s
speed after batter hit the ball(V f) = - 48 m/s
a)
impulse = change in momentum
=
=
= -12.6 Kg m/s
Magnitude of impulse = 12.6 Kg m/s
b)
Force =
=
Force = 2520 N
Electrical energy is used to run the fan
Here as per given condition 750 J of electrical energy is used to run the fan which is converted into Kinetic energy as 400 J
So here we can see that 350 J of energy is lost against many other type of frictional and resistive loses.
So here we can say that out of 750 J of energy only 400 J is used to run the fan and rest amount of energy is lost against friction.
also we can say that efficiency of this fan will be
High task repitition, forceful exertions, repetitive or sustained awkward posture
1km=10^3 m,1km^3=10^9cubic metres answer is 1.4x10^18cubic meters
TRUE. When you approach a yield sign, while trying to enter or merge onto another road, traffic already on that road has the right of way.