KE = ½mv² = ½(4.00 kg)(16.0 m/s)² = 512 J
Answer: 15m/s
Explanation: <u>Average</u> <u>Velocity</u> is vector describing the total displacement of an object and the time taken to change its position. It is represented as:
At t₁ = 1.0s, displacement x₁ is:
x(1) = 28
At t₂ = 4.0s:
x(4) = 73
Then, average speed is
v = 15
The average velocity of a car between t₁ = 1s and t₂ = 4s is 15m/s
Acceleration= change in velocity/time; 5/2.8 , so a=1.785714286
C. A cold front that came through does not affect the climate of an area.
Acceleration = (change in speed) / (time for the change)
Change in speed = (speed at the end) minus (speed at the beginning.
The cart's acceleration is
(0 - 2 m/s) / (0.3 sec)
= ( -2 / 0.3 ) (m/s²) = -(6 and 2/3) m/s² .
Newton's second law of motion says
Force = (mass) x (acceleration) .
For this cart: Force = (1.5 kg) x ( - 6-2/3 m/s²)
= ( - 1.5 x 20/3 ) (kg-m/s²)
<span> = </span>- 10 newtons .
<span>The force is negative because it acts opposite to the direction </span>
<span>in which the cart is moving, it causes a negative acceleration, </span>
<span>and it eventually stops the cart.</span>