Answer:
The velocity 13.4 must be squared then divided by the kinetic energy to get the height of 15.7 ht
Explanation:
False, as an object falls its potential energy turns into kinetic energy thus decreasing the potential energy.
The speed of the tennis ball is 8 km/h when Alana throws the ball behind at the speed of 11 km/h.
<h3>What is the
frame of
reference?</h3>
It is a point from where the motion is observed. The speed changes with the frame of reference.
For the person standstill on the sidewalk, If Alana throw the ball in the front direction, The speed will be,
19+11 = 30 km/h
It Alana just leave the ball, the speed,
19 +0 = 19 km/h
If Alana throws the ball behind her at the speed of 19 km/h. The speed of the ball for a sidewalk observer,
19 +(-19 ) = 0 km/h
Thus, when Aana throw the ball behind the velocity will be negative,
So,
19 + (-11 ) = 8 km/h
Therefore, the speed of the tennis ball is 8 km/h when Alana throws the ball behind at the speed of 11 km/h.
Learn more about Frame of reference:
brainly.com/question/9820962
Answer:
Explanation:
Average velocity is found in the total displacement experienced in the trip divided by the total time it took to make this trip. If, for the first 2.0 hours, the car travels at 60 km/hr, then in 2.0 hours the car can travel 120 km; if it then travels for 3.0 at 85 km/hr, it can travel 255 km in the same direction. The total time this took was 5.0 hours. So doing the math and rounding correctly by following the rules for the adding and subtracting of sig fig's:
If you do not round when you add, the average velocity is 75 km/hr
