Question

the amount of work done in lifting a brick to a high of 10 m is 980J calculates the mass of the bricks​

Answer 1

Provided that:

• Height = 10 m
• Work done = 980 J

To calculate:

• Mass

Solution:

• Mass = 9.8 kg

Using concept:

• Work done formula

Using formula:

• W = Fs

Where, F denotes force, W denotes work done and s denotes displacement.

Required solution:

»»» Work done = Force × Displacement

»»» W = Fs

»»» W = m × a × s

»»» W = m × g × s

{Here g is acceleration due to gravity. We know that 9.8 m/s sq. is the universal value for g but here we are taking it in approx as 10 m/s.}

»»» 980 = m × 10 × 10

»»» 980 = m × 100

»»» 980/100 = m

»»» 98/10 = m

»»» 9.8 = m

»»» m = 9.8 kg

»»» Mass = 9.8 kg

• Therefore, mass of brick = 9.8 kg

Now let's verify!

»»» Work done = Force × Displacement

»»» W = Fs

»»» W = m × a × s

»»» W = m × g × s

»»» 980 = 9.8 × 10 × 10

»»» 980 = 9.8 × 100

»»» 980 = 980

»»» LHS = RHS

• Henceforth, verified! $\:$