Question

An object of mass 100 kg is accelerated uniformly from a velocity
of 5 m s' to 8 m s' in 6 s. Calculate the initial and final
momentum of the object. Also, find the magnitude of the force
exerted on the object,​

Answer 1

Answer:

mass (m) = 100 kg , initial velocity (u) = 5m/s , final velocity (v) = 8m/s ,

calculate the initial and final momentum of the object and the force exerted

Explanation:

the momentum (p) = p1 -p2

p1= mu

   = 100 ×5=500 kg m/s

p2=mv

    = 100×8=800 kg m/s

change in momentum = p2 -p1

                                     = 800-500=300 kg m/s

Answer 2

$\bf{\underline{\underline{Answer:}}}$

$\bf{\therefore 50\:N}$

$\bf{\underline {Given:}}$

Initial velocity, $u \:=\:5\:{s}^{-1}$

Final velocity, $v \:=\:8\:{s}^{-1}$

Mass of the given object, $m = 100\:kg$

Time, $t\:=\:6\:s$

$\bf{\underline {To\:Find:}}$

Initial momentum and final momentum =?

Magnitude of force exerted on the object =?

We know that,

Momentum, p = Mass × Velocity

Therefore, initial momentum,

= Mass × Initial velocity

${100×5=500\:kg \:m\:{s}^{-1}}$

Final momentum,

= Mass × Final velocity

${100×8=800\:kg\:m\:{s}^{-1}}$

$<b>To find the magnitude of the force exerted on the object :</b>$

We know that,

$v \:= \:u \:+ \:at$

$8 \:= \:5 \:+ \:a\:×\:6$

$8 \:-\:5 \:= \:a\:×\:6$

$a =\dfrac{3}{6}\:=\:0.5\:m\:{s}^{-2}$

Now, force exerted on object

= Mass × Accleration

= 109 × 0.5

$= \bf{50\:N}$