Answer:
Explanation:
Assuming no friction between the roller coaster car and the hill, and neglecting air resistance, the kinetic energy the roller coaster car would have at the bottom of the hill would be equal to its gravitational potential energy at the top of the hill, by conservation of energy.
We assume that horn releases sound of constant frequency. In order for observer to observe different frequency either horn or observer or both must move.
This happens due to Doppler effect. It states that when position of source of sound and observer relative to each other changes, the observed frequency also changes. If the source emits sound of constant frequency than observed frequency will be either higher or lower than original.
When distance between source and observer increases the observed frequency will be lower. This is because same number of sound waves must cover greater distance so they have greater wavelength.
When distance between source and observer decreases the observed frequency will be higher. This is because same number of sound waves must cover smaller distance so they have smaller wavelength.
Wavelength and frequency are inversely proportional meaning when one increases the other drecreases.
From this explanation we can find answer for our question. <span>If we wanted the pitch of a horn to drop relative to an observer we need to move horn away from an observer.</span>
Answer:a. 24 kg m/s
b. 3/5s
Explanation:
a.impulse is the change in momentum so at first the momentum is zero because the ball was at rest and the final momentum is 1.2kg*20m/s=24 kg m/s
so the impulse would be (24-0) kg m/s=24 kg m/s
b. so the impulse equation is impulse is force *delts time
so 24 kg m/s=40N*t
t=24 kg m/s /40N=3/5 s
D. <span>Johannes Kepler argued that Earth was the center of the universe.
</span>
The answer will be 50N.
This is because the spring reads weight and weight is mass times acceleration due to gravity.5kg*10m/s2=50N
