Question

answer this urgent fast tommarow my exam​

Answer 1

Power = 100 watts

u = 10 m/s

v = - 5 m/s

t = 4 sec

m = 1000 kg

Work = ?

Initial kinetic energy = ?

Final kinetic energy = ?

Work = m/2 ( v×v - u×u)(Work energy theorem )

=1000/2(5×5-(-10×-10)

= 500 (25-100)

= 500×75

=37500 J

Initial kinetic energy = m×u×u/2

=1000 ×10 ×10 /2

=100000/2

=50000 J

Final kinetic energy = m×v×v/2

=1000×-5×-5/2

=25000/2

=12500 J