Answer:
(a) the runner's kinetic energy at the given instant is 308 J
(b) the kinetic energy increased by a factor of 4.
Explanation:
Given;
mass of the runner, m = 64.1 kg
speed of the runner, u = 3.10 m/s
(a) the kinetic energy of the runner at this instant is calculated as;
(b) when the runner doubles his speed, his final kinetic energy is calculated as;
the change in the kinetic energy is calculated as;
Thus, the kinetic energy increased by a factor of 4.
The impulse exerted on the ball by the wall is 24i kgm/s.
<h3>
Impulse exerted by the ball on the wall</h3>
The impulse exerted by the ball on the wall is the change in the linear momentum of the ball.
J = ΔP
ΔP = Pf - Pi
P = mv
where;
- m is mass of the ball
- v is the velocity
ΔP = 3(4.0i + 3.0j) - 3(-4.0i + 3.0j)
ΔP = (12i + 9j) - (-12i - 9j)
ΔP = 24i kgm/s
Thus, the impulse exerted on the ball by the wall is 24i kgm/s.
Learn more about impulse here: brainly.com/question/904448
#SPJ1
Answer:
acceleration of car B appears at slowing down by 16 km/h each second
Explanation:
As we know by the concept of relative acceleration
now we know that
Car A is moving with speed 100 km/h such that its speed is increasing at rate of 8 km/h each second
so acceleration of car A is given as
now car B is also moving at same speed of 100 km/h but its speed is slowing down at rate of 8 km/h each second
so acceleration of car B is negative as it is decelerating
So here we have from above formula
so acceleration of car B appears at slowing down by 16 km/h each second