Velocity is directly proportional to Time.
If the acceleration is constant (negative or positive) the instantaneous acceleration cannot be
Average acceleration: [final velocity - initial velocity ] /Δ time
Instantaneous acceleration = d V / dt =slope of the velocity vs t graph
If acceleration is increasing, the slope of the curve at one moment will be higher than the average acceleration.
If acceleration is decreasing, the slope of the curve at one moment will be lower than the average acceleration.
If acceleration is constant, the acceleration at any moment is the same, then only at constant accelerations, the instantaneuos acceleration is the same than the average acceleration.
Constant zero acceleration is a particular case of constant acceleration, so at constant zero acceleration the instantaneous accelerations is the same than the average acceleration: zero. But, it is not true that only at zero acceleration the instantaneous acceleration is equal than the average acceleration.
That is why the only true option and the answer is the option D. only at constant accelerations.
Answer:
800
cm²
Explanation:
Given parameters:
radius of the coin = 20cm
Unknown:
Surface area of the coin = ?
Solution:
A coin is made up of two faces;
Surface area = 2(πr²)
Insert the parameters and solve;
Surface area = 2(
)
Surface area = 800
cm²
Answer:
t=7.33 s
Explanation:
According to Newton's second law:

because we don't want the box to slide, the acceleration has to be zero.

we know that:

Now having the acceleration, we can use the following formula.
