A20 kg mass with an initial velocity of 10 m/s slides to a stop in 2 meters. what is the net work down on the mass? a.) 250 j b.) 500 j c.) 120 j d.) 20 j e.) none of the above

12500 J

Explanation:

m = 20 kg, u = 10 m/s, s = 2 m, v = 0

Use third equation of motion

v^2 = u^2 = 2 a s

0 = 100 - 2 a x 2

100 / 4 = - a

a = - 25 m/s^2

Force, F = m a = 20 x 25 = 500 N

Work done = F x s = 500 x 25 = 12500 J

answer: 802.3 kilo joules of energy represents 191.75 kilo calorie of energy.

explanation:

energy released during combustion of one mole methane = 802.3 kilo joules

if 1 kilo joule = 0.239006   kilo calorie

then ,802.3 kilo joule will be = 802.30.239006 kilo calorie

802.3 kilo joule = 191.75 kilo calorie

hence, the energy in kilo calorie is 191.75 kilo calorie.

overcharge is the right answer system