Question

Aril does 1800 J of work to get a canoe moving from rest. April and the canoe have a mass of 70 kg.

Answer 1

a) KE=energy required to make them move=1800J

b) KE=1/2*mv^2, so $v=\sqrt{\frac{2KE}{m}}=7.17$ J

Answer 2

Answer:

a) KE = 1800 J

b) v = 7.17 m/s

Explanation:

Part a)

As we know by work energy theorem that work done by all force is always equal to change in kinetic energy of system

here we have

$W = KE_f - KE_i$

given that

initial kinetic energy = 0

work done = 1800 J

so final kinetic energy will be

$KE = 1800 J$

part b)

now we know that

$KE = \frac{1}{2}mv^2$

now from above equation we have

$1800 = \frac{1}{2}(70)v^2$

$v^2 = \frac{1800}{35}$

now from above we have

$v = 7.17 m/s$