Yes. Think of block sitting on top of a bigger block. If the bottom block moves, it will drag the top block with it. Since the force of friction on the small block and its displacement are in the same direction, the "work" is positive. The static friction is a passive force, It is not a source of energy; it transmits the force placed on the bottom block. (And the "work" done by the friction on the bottom block is exactly the negative of the work done on the top block.)
<h3><u>Answer</u>;</h3>
C. An object can have acceleration with negative velocity.
<h3><u>Explanation</u>;</h3>
- Acceleration is a measure of the change in velocity over time. The change in velocity is measured in meter per second (m/s), and time interval is measured in second (s).
- Therefore, acceleration measures the change in meters per second every second [(m/s)/s], namely meters per second per second or meters per second squared (m/s2).
- If an object has zero acceleration, its velocity doesn’t have to be zero. Acceleration is a measure of the change in velocity over time. Zero acceleration means there is no change in velocity over time, namely constant velocity.
The force between two objects is calculated through the equation,
F = Gm₁m₂/d²
where m₁ and m₂ are the masses of the objects. In this case, an unknown mass and Earth. d is the distance between them and G is universal gravitation constant.
In the second case, if the force is to become 2.5 times the original and all the variables are constant except d then,
2.5F = Gm₁m₂ / (D²)
D = 0.623d
Subsituting the known value of d,
D = 0.623(6.9 x 10^8) = <em>4.298 x 10^8 m</em>
False, its not true so don'
t put it on you paper
Linear expansivity is the fractional increase in length of a specimen of a solid, per unit rise in temperature.
