Answer:
75 kgm/s
Explanation:
Impulse: This can be defined as the product of mass and change in velocity. The S.I unit is kgm/s.
From the question,
I = m(v-u)................... Equation 1
Where I = impulse, m = mass, v = final velocity, u = initial velocity.
Let the direction of the initial velocity be the positive direction.
Given: m = 5 kg, v = -10 m/s (bounce off), u = 5 m/s.
Substitute into equation 1
I = 5(-10-5)
I = 5(-15)
I = -75 kgm/s.
The negative sign tells that the impulse act in the same direction as the final velocity of the ball
Hence,
I = 75 kgm/s
The object is fixed relative to the motion you are trying to describe.
Answer:
the preview of the scientific method
<span>So this question based on doppler effect
Here apparent freq = freq of sound *(speed of sound-speed of observer)/(speed of sound-speed of source)
given
freq of sound=2000
speed of observer= 20
speed of source= 30
taking speed of sound as 343 m/s
apparent freq = 2000 [343 - 20] / [343 - 30] = 2063.90 Hz</span>