Answer:
(a) <em>change in momentum of the car = 21760 kgm/s</em>
(b) <em>The magnitude of the force = 306.48 N</em>
Explanation:
<em>(a)</em>
<em>Change in momentum: </em><em>This is the product of mass and change in velocity. The unit of momentum is kgm/s. It can be expressed mathematically as,</em>
Change in momentum of the car = m(v-u)................. Equation 1
Where m = mass of the car, v = final velocity of the car, u = initial velocity of the car.
<em>Given: m = 640 kg, v = 44.0 m/s, u = 10.0 m/s.</em>
<em>Substituting these values into equation 1,</em>
<em>Change in momentum of the car = 640 (44-10)</em>
<em>change in momentum of the car = 640× 34</em>
<em>change in momentum of the car = 21760 kgm/s</em>
<em>change in momentum of the car = 21760 kgm/s</em>
<em>(b) Force:</em><em> Force of a body can be defined as the product of mass and its acceleration. It is measured in Newton (N). It can be expressed mathematically as,</em>
<em>Force = ma ................................ Equation 2</em>
<em> </em><em> Or</em>
<em>Force = m(v-u)/t...................................... Equation 3</em>
<em>Where m = mass of the car, v = final velocity of the car, u = initial velocity of the car, a = acceleration of the car, t = time taken to change the velocity.</em>
<em>Given: m = 640 kg, u = 10.0 m/s v = 44 m/s, t = 71 s.</em>
<em>Substituting these values into equation 3</em>
<em>Force = 640(44-10)/71</em>
<em>Force = (640×34)/71</em>
<em>Force = 306.48 N</em>
<em>The magnitude of the force = 306.48 N</em>
by the equation