Question

6. If the work done by a body on application of a constant force is directly proportional
to the distance travelled by the body, express this in the form of an equation in two
variables and draw the graph of the same by taking the constant force as 5 units. Also
read from the graph the work done when the distance travelled by the body is
(i) 2 units
(ii) 0 unit
​

Answer 1

x 0 2 3

y 0 5 10

Let x units be the distance traveled by the body and y units be the work done by constant force.

According to problem, y=5x ...(1)

Now , putting the value x=0 in (1)

y=5×0=0

So, the solution is (0,0)

Putting the value x=1 in (1)

y=5×1=5

So, the solution is (1,5)

Putting the value x=2 in (1)

y=5×2=10

So, the solution is (2,10)

(i) When x=2 units (distance)

Putting the value x in (1)

y=5x

y=5×2=10.

Hence, Work done =10.

(ii) When x=0 units (distance)

Putting the value x in (1)

y=5x

y=5×0=0.

Hence, work done =0.