Answer:
17.64 km/h
Explanation:
mass of car, m = 1000 kg
Kinetic energy of car, K = 1.2 x 10^4 J
Let the speed of car is v.
Use the formula for kinetic energy.

By substituting the values

v = 4.9 m/s
Now convert metre per second into km / h
We know that
1 km = 1000 m
1 h = 3600 second
So, 
v = 17.64 km/h
Thus, the reading of speedometer is 17.64 km/h.
Answer: When a liquid or gas is heated, the molecules move faster, bump into each other, and spread apart. Because the molecules are spread apart, they take up more space. ... The molecules move more slowly and take up less space. Therefore temperature can affect density.
Explanation:
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Answer:</h2>
<u>A. A nuclear power plant</u> produces radioactive wave.
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Explanation:</h2>
A plant in which a nuclear reactor is used as a source to produce heat is known as nuclear power plant. The heat formed by the reactor is used to form steam which can be used to drive turbines to produce electricity.
The coolant in reactor gets heated by the fission process taking place in the reactor. It is a cyclic process where the steam is condensed and reverted back. A nuclear power plant in active condition produce a small amount of radiation which can be sensed within a radius of 50 miles.
No matter what direction you throw it, or with what speed, its acceleration is immediately 9.8 m/s^2 downward as soon as you release it from your hand, and it doesn't change until the ball hits something.