Answer:
You can describe the<u> motion </u>of an object by saying it is moving in a straight line or is curved around another object. You can also describe where an object is by its <u> position </u> in relation to another object. The second object acts as a<u> reference</u> point. When an object changes position, you know it has motion. Motion can also be described by finding an object's <u>speed </u>or how fast or slow it moves in a certain amount of time. In addition, you can describe the object's speed AND direction together. This is called <u>velocity</u>
Explanation:
In the given answer-
<u>Motion</u> is defined as - the change in the movement or position of any object or body.
<u>Position</u> is said to be a place or somewhere or a location where any object or body is particularly placed/located or put on.
<u>Reference poin</u>t is a fixed point with regards to which any object or body changes its position. It is also called reference origin.
<u>Speed</u> is defined as the rate of any object covering certain distances. It is a scaler quantity (quantity which depends upon only magnitude).
<u>Velocity</u> is defined as the rate of speed per unit time. It is a vector quantity (quantity depending upon both magnitude and direction ).
Hello!
In a thermostat, the property of the bimetallic coil that allows it to contract and expand is that The two metals absorb different amounts of thermal energy.
This bimetallic coil is used to transform thermal energy into mechanical movement. Two metals with different thermal expansivity are joined together parallelly and the changes of temperature cause bending in different directions depending on if the temperature is rising or descending.
The differences in the thermal energy absorption of the two metals are the basis for the mechanism of this device.
If the 30 N on the rope were pulled straight up, it would offset the force of gravity ( m g = 10 kg * 9.8 N/kg = 98 N) , leaving a net force up from the ground on the sled of 98-30 = 68 N. Since the rope is pulled at the angle of 25o, only part of the force is in the upward direction, (30N)(sin(25) = (30)(.423) = 12.7. So the net force becomes 98 N down offset by 12.7 up or 98-12.7 = 85.3 N. Ah, there it is: C.
