Question

An object of mass 50 kg is accelerated uniformly from a velocity of 5m/s to 11 m/s in 6 seconds.Calculate the change in the momentum of the object.Also, find the magnitude of the force exerted on the object

Answer 1

Explanation:

Mass of the object (m) = 50kg

Time = 6 seconds

Initial velocity (u) = 5m/s

Initial momentum = mu

= Mass × Initial velocity

= 50 × 5

= 250Ns

Initial momentum = 250Ns

Final velocity (v) = 11m/s

Final momentum = mv

= Mass × Final velocity

= 50 × 11

= 550

Final momentum = 550Ns

Change in momentum = mv - mu

= 550 - 250

= 300Ns

∴ Change in momentum = 300Ns

Force exerted on the object = $\rm \dfrac{mv - mu}{t}$

= $\dfrac{300}{6}$

= 50N

∴ Force exerted on the object = 50N

Answer 2

AnswEr :

• Mass (m) = 50 kg
• Initial velocity (u) = 5 m/s
• Final velocity (v) = 11 m/s
• Time = 6s

$\frak{To\ Find} \begin{cases} \sf{Change\ in\ momentum} \\ \\ \sf{Force} \end{cases}$

➝ Δp = m(v - u)

➝ Δp = 50(11 - 5)

➝ Δp = 50(6)

➝ Δp = 300 kgm/s

_______________________

➝ F = Δp/Δt

➝ F = 300/6

➝ F = 50 N