Question

calculate the work done in lifting 300 N weight to height of 10 m with acceleration 0.5 m/s^2
g=10 m/s^2
ans) 3150 J​

Answer 1

Given:

• Weight = 300 N

• Height, h = 10 m

• Acceleration, a = 0.5 m/s²

• Acceleration due to gravity, g = 10 m/s²

To be calculated:

Calculate the work done?

Formula used:

• W = m × g

• Work done = m × g × h

Solution:

We know that,

W = m × g

★ Substituting the values in the above formula,we get

⇒ 300 = m × 10

⇒ m = 300/10

⇒ m = 30 kg

Total acceleration of body ( a ' ) = a + g

= 0.5 + 10

= 10.5 m/s²

Now,

Work done = m × a' × h

★ Putting the values in the above formula

Work done = 30 × 10.5 × 10

= 30 × 105

= 3150 J

Hence, the work done is 3150 joules

Answer 2

Answer :

3150 J work has been done in lifting 300 N weight to a height of 10 m with acceleration 0.5 m/s².

$\rule{100}2$

Explanation :

It is given that,

• Weight = 300 N
• height ( h ) = 10 m
• acceleration ( a ) = 0.5 m/s²
• Value of ' g ' = 10 m/s²

Now,

In order to find the work done by the body, we've to find it's mass and total acceleration acting on the body. And then finally, substitute the values in the formula :-

• Workdone = mgh

∵ weight = mg

→ 300 = m × 10

→ m = 300/10

∴ mass = 30 kg

TOTAL ACCELERATION ACTING ON THE BODY :

→ 0.5 m/s² + 10 m/s²

→ 10.5 m/s²

Finally, substitute these values in the formula. We get,

workdone = 30 kg × 10.5 m/s² × 10  m

→ workdone = 30 × 105

∴ workdone = 3150 J

$\rule{200}2$