A 550 kg dragster accelerates from rest to a final speed of 110 m/s in 400 m (about a quarter of a mile) and encounters an average frictional force of 1200 N. What is its average power output in watts and horsepower if this takes 7.30 s

Explanation:

According to the energy conversation:

ΔK=

ΔK=

where,

are initial and final kinetic energy of the system.

= initial velocity of the system

=final velocity of the system

W= total work done on the system

= friction force

d= distance traveled

Given: =110m/s

d=400m

=1200N

=0m/s

t=7.3s

ΔK=

W= ΔK +

  =

answer: 2×10^-2kg

explanation: density= mass per volume

vol=mass/density

converting to s.i units we have;

3÷1000kg = 0.003

1.5÷100m = 0.15

0.003/0.15 = 0.02kg

it's a b and