Question

A ladder of mass 30kg and length 6m resting of level floor is lifted and held against wall at an angle of 60 degree with floor then work done by gravitional force is

Answer 1

Given :-

Mass of ladder = 30 Kg

Length of ladder = 6 m

$\theta = 60°$

As we know that,

Wg = mg ScosØ

Wg = 30(10) × 6 × 1/2

Wg = 300 × 3

Wg = 900 J

Answer 2

Answer:

Work done by gravitational force is $882J$.

Explanation:

Given that :

Mass of ladder $= 30 Kg$

Length of ladder $= 6 m$

Angle θ $= 60^0$

If the angle is $60^0$ then the value of $cos$ θ $=\frac{1}{2}$

Acceleration due to gravity $=9.8 m/s^2$

We know that the formula for work done $=$ Force * displacement

If the angle is given, then work done = force * displacement * $cos$ θ

force $= mg$

work done $= mg* s* cos$ θ

$=30*9.8*6*\frac{1}{2}$

$=882J$