Answer:
<u>The car's average speed is 32 kilometers per hour</u>
Explanation:
1. Let's review the information given to us to answer the question correctly:
First two hours = 60 kilometers
Next two hours = 68 kilometers
2. What is the car's average speed?
Total distance traveled by the car = 60 + 68
Total distance traveled by the car = 128
Total time of travel = 2 + 2 hours
Total time of travel = 4 hours
Average speed = Total distance/Total time
Replacing with the real values, we have:
Average speed = 128/4
<u>Average speed = 32 kilometers per hour</u>
Answer:
gravity, also called gravitation, in mechanics, the universal force of attraction acting between all matter. ... On Earth all bodies have a weight, or downward force of gravity, proportional to their mass, which Earth's mass exerts on them. Gravity is measured by the acceleration that it gives to freely falling objects.
Answer:
Explanation:
When the skier reaches the bottom of the slope , height lost by it
h = 50 sin32 m
= 26.5 m
potential energy lost
= mgh
Gain of kinetic energy
= 1/2 mv²
mgh = 1/2 mv²
v = √ 2gh
= √ (2x9.8 x 26.5)
= 22.8 m /s
b )
Let μ be the coefficient of kinetic friction required.
friction force acting
= μmg
work done by friction in displacement of d (40 m ) on horizontal surface
- μmg x d
This negative work will be equal to positive kinetic energy of the skier on horizontal surface .
= μmg x d = (1/2) m v²
μ = v² / (2 gd)
= 519.4 / (2 x 9.8 x 140 )
= .19
To solve this problem it is necessary to apply the concepts related to Newton's second law and its derived expressions for angular and linear movements.
Our values are given by,
If we carry out summation of Torques on the pulley we will have to,
Where,
I = Inertia moment
Angular acceleration, which is equal in linear terms to a/r (acceleration and radius)
The moment of inertia for this object is given as
Replacing this equations we have know that
Or
Replacing our values we have that
Therefore the tension in the string between the pulley and the cart is 0.974 N
We would need to know the time it took to slow to a stop.
