Answer:8.3m/sec 30 sec,
Explanation:
A student practicing for a track meet, ran 250 m in 30 sec. a. What was her average speed? 250 m = 8.3 m/sec 30 sec.
The stopwatch will be the most useful in determining the kinetic energy of a 50 g battery- powered car traveling a distance of 10 m.
<h3>What is kinetic energy?</h3>
Kinetic energy is the energy of a body possessed due to motion.
This means that for an object to possess kinetic energy, it must be in motion.
The kinetic energy is measured in Joules, which is a product of the mass of the substance and the time taken to travel a distance.
A stopwatch is an instrument used to measure time as one of the components of kinetic energy.
Therefore, the stopwatch will be the most useful in determining the kinetic energy of a 50 g battery- powered car traveling a distance of 10 m.
Learn more about kinetic energy at: brainly.com/question/12669551
Answer:
the speed of the ball is 10 m/s
Explanation:
Given;
magnitude of exerted force, F = 400 N
mass of the ball, m = 2 kg
radius of the circle, r = 0.5
The speed of the ball is calculated by applying centripetal force formula;

Therefore, the speed of the ball is 10 m/s
I think the answer should be: “100.4957 N”