Explanation:
We have,
Distance traveled in a circular track is 500 miles
The winning time was 3 hours and 13 minutes. It means time is 3.217 hours.
The driver's average speed is given by total distance divided by total time taken. Its formula can be written as :

At the end of the race, the driver reaches the point form where he has started. It means the displacement of the driver is equal to 0. Hence, driver's average velocity is equal to 0.
Answer:
Natalie says that all things with mass have a gravitational field, but the force is very weak and cannot be perceived around small objects.
Explanation:
The force due to gravity is proportional to the mass of the object and inversely proportional to the square of the distance between objects. The Earth is so massive that the force due to its gravity is much greater than the force between objects on the counter.
If there were no friction, the objects might move toward each other, depending on what other masses were near them tending to cause them to move in other directions.
Natalie's explanation is about the best.
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<em>Additional comment</em>
The universal gravitational constant was determined by Henry Cavendish in the late 18th century using lead balls weighing 1.6 pounds and 348 pounds. His experiment was enclosed in a large wooden box to minimize outside effects. While these masses are somewhat greater than those of a glue bottle and stapler, the experiment shows the force of gravity between "small" objects <em>can</em> be measured.
Electric motors require electricity to move the motor parts and do work (like an electric fan).
Elecgric generators actually burn diesel fuel to spin a motor around and around and around to GENERATE, or MAKE, electricity that you can then use to power your fans and lights in your house.
Linear momentum has to be conserved. It was zero before the thread eas burned ... when nothing was moving ... so the momentum of the masses moving in opposite directions has to add up to zero. ... Momentum = mass times speed. ... In one direction, you have 5 kg times 1/5 m/s= 1 kg-m/s. ... We need 1 kg-m/s in the other direction. ... 7 kg times speed = 1 kg-m/s. ... Can you finish it from here ?