Give u = start velocity
v = end velocity
v = u + at
50 = 400 + a*30
30a = -350
a = -116.67 m/
**Why the accecleration is negative number**
Because displacement, velocity, and acceleration are VECTOR QUANTITIES.
Vector Quantity must have direction.
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>
Answer:
The perimeter of the rectangle is 60 units.
Explanation:
The perimeter of a rectangle is given by the equation P = 2L + 2W. With W = 12 units and L = 18 units, substituting the values in the equation above:
P = 2(18 units) + 2(12 units)
P = 36 units + 24 units
P = 60 units