Question

2. If you exert a force of 10.0 N to lift a box a distance of 0.9 m, how much work have you done?

Answer 1

 force of 10.0 N

distance of 0.9 m
w=f*d
w=10*0.9
=9.0 j

Answer 2

Answer :

(2) The work done is, 9.0 J

(3) The power of a machine measures  its rate of doing work.

(4) The power used, 700 W

(5) A 750-W motor might also be rated as a  1-horsepower motor.

Solution for part (2) :

Formula used : $W=F\times d$

where,

W = work done = ?

F = applied force = 10 N

d = displacement = 0.9 m

Now put all the given values in the above formula, we get the work done.

$W=(10N)\times (0.9m)}=9J$

Therefore, the work done is, 9.0 J

Explanation for part (3) :

Power : it measures the rate of doing work by time.

Formula for power is, $Power=\frac{Work}{time}$

Solution for part (4) :

Formula used : $P=\frac{W}{t}=\frac{F\times d}{t}$

where,

W = work done

F = applied force = 700 N

d = displacement = 6 m

t = time taken = 6 s

Now put all the given values in the above formula, we get the work done.

$P=\frac{700N\times 6m}{6s}=700W$

Therefore, the power used, 700 W

Solution for part (5) :

As, 746 watt is equal to 1 horsepower

So, 750 watt is equal to $\frac{750}{746}=1.005=1\text{ horsepower}$

Therefore, a 750-W motor might also be rated as a  1-horsepower motor.