(a)
consider the motion of the tennis ball. lets assume the velocity of the tennis ball going towards the racket as positive and velocity of tennis ball going away from the racket as negative.
m = mass of the tennis ball = 60 g = 0.060 kg
v₀ = initial velocity of the tennis ball before being hit by racket = 20 m/s
v = final velocity of the tennis ball after being hit by racket = - 39 m/s
ΔP = change in momentum of the ball
change in momentum of the ball is given as
ΔP = m (v - v₀)
inserting the above values
ΔP = (0.060) (- 39 - 20)
ΔP = - 3.54 kgm/s
hence , magnitude of change in momentum : 3.54 kgm/s
Answer:
chloride, ion, -1, this is an anion
The formula relating frequency and period of a wave is simply frequency = 1 / time. Therefore, by rearranging we also see that time = 1 / frequency. The period of a 440 Hertz sound wave is 1 / 440 seconds. The speed of the wave can also be determined very simply using the formula speed = wavelength x frequency.
Answer:
Magnitude 900m/s, direction 12.8° respect to the velocity of the first asteroid.
Explanation:
This is a perfectly inelastic collision, because the two asteroids stick together at the end. That means that the kinetic energy doesn't conserves, but the linear momentum does. But, since the velocities of the asteroids have different directions, we have to break down them in components. For convenience, we will take the direction of the first asteroid as x-axis, and its perpendicular direction (in the plane of the two velocity vectors) as y-axis. So, we have that:

And, since
, we get:

Solving for v_fx and v_fy, and calculating their values, we get:

Now, the final speed can be calculated using the Pythagorean Theorem:

And the direction
can be obtained using trigonometry:

That means that the final velocity of the two asteroids has a magnitude of 900m/s and a direction of 12.8° with respect to the velocity of the first asteroid.