Answer:
4 A
Explanation:
The relationship between current, voltage and resistance in a circuit is given by Ohm's law:

where
V is the voltage
R is the resistance
I is the current
The equation can also be rewritten as

from which we see that the current is inversely proportional to the resistance, R.
In this problem, the initial current is I = 8 A. Then the resistance is doubled:
R ' = 2R
So the new current is

so the current is halved.
The total amount of energy stays the same, but throughout the ride, the kinetic energy and the potential energy change, still adding up to the same number. At the top of the ride it has potential energy, and as it goes down the potential energy decreases and the kinetic energy increases. When it’s at the bottom of the first drop it has maxed out its kinetic energy, and minimized its potential energy. Friction slows down the car, and pushes on the cart with a force that is equal and opposite to the force being exerted in the track. The reason the track keeps going is because though it exerts and equal and opposite force the momentum of the objects is different, allowing the car to continue moving, however friction will slow it down until eventually it comes to a stop.
Basically it is the difference in velocity divided by the time it takes to make that change.
A. To show how precise your measurements were
Explanation:
It is important to use the correct number of significant digits when reporting the results of an experiment because they show how precise measurement are.
- Precision is the ability to reproduce a particular set of results in an experiment.
- Every instrument have their precision level.
- The precision levels shows to what extent the values obtained can be trusted..
- Significant figures are not only important in recording measurements, they are also needed for calculations in science.
Learn more:
Significant figures brainly.com/question/4967602
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A compound machine uses more than one simple machine to work. The six classic examples of simple machines are: Lever, wheel/axle, pulley, inclined plane, wedge, and a screw.
A ramp is an inclined plane. Therefore, the answer is D. a pair of scissors