Question

class 9 chapter force and law of motion​

Answer 1

Answer:

Given,

Mass = 50 kg

Acceleration = 2 m/s²

Force = Mass * Acceleration

= 50 * 2

= 100 kgm/s²

= 100 N Ans.

Ans.) 100 N force will be required to speed up the object.

Answer 2

Provided that:

• Acceleration = 10 m/s²
• Force = 50000 Newton

To calculate:

• Mass of the vehicle

Solution:

• Mass of the vehicle = 5000 kg

Using concept:

• Force formula

Using concept:

• F = ma

(Where, F denotes force, m denotes mass of the body and a denotes acceleration)

Required solution:

~ We just have to put the values according to the formula, and have to carry on!

$:\implies \sf Force \: = mass \times acceleration \\ \\ :\implies \sf F \: = m \times a \\ \\ :\implies \sf F \: = ma \\ \\ :\implies \sf 50000 \: = m(10) \\ \\ :\implies \sf 50000 \: = m \times 10 \\ \\ :\implies \sf \dfrac{50000}{10} \: = m \\ \\ :\implies \sf \cancel{\dfrac{50000}{10}} \: = m \\ \\ :\implies \sf 5000 \: = m \\ \\ :\implies \sf m \: = 5000 \: kg \\ \\ :\implies \sf Mass \: = 5000 \: kg \\ \\ {\pmb{\sf{Henceforth, \: solved!}}}$

Verification:

~ Now let us check out our result!

$:\implies \sf Force \: = mass \times acceleration \\ \\ :\implies \sf F \: = m \times a \\ \\ :\implies \sf F \: = ma \\ \\ :\implies \sf 50000 = 5000(10) \\ \\ :\implies \sf 50000 = 5000 \times 10 \\ \\ :\implies \sf 50000 = 50000 \\ \\ :\implies \sf L.H.S \: = R.H.S \\ \\ {\pmb{\sf{Henceforth, \: verified!}}}$

Our result is fully correct!