Answer:
98J
Explanation:
Given parameters:
Mass of rock = 5kg
Height = 2m
Unknown:
Work done = ?
Solution:
The amount of work done is given as:
Work done = Force x distance
Work done = Weight x height
Work done = mgH
Now insert the parameters and solve;
Work done = 5 x 9.8 x 2 = 98J
- Initial velocity=20m/s
- Final velocity=0m/s(As the car stops)
- Acceleration=-8m/s^2
- Distance=s=26m
We need to verify the thrid equation of kinematics here





The squirrel has a good luck ,Car gets stopped just 1m away from the squirrel .
Answer:
Friction produces unnecessary heat leading to the wastage of energy. The force of friction acts in the opposite direction of motion, so friction slows down the motion of moving objects. Forest fires are caused due to the friction between tree branches. However, friction can also cause problems in a car. Friction between moving engine parts increases their temperature and causes the parts to wear down. Friction can be both harmful and helpful, so it may be necessary to decrease or increase friction.
The both have the unit (J) for Jules
B is the answer because it takes millions of years to form these fossil fuels and everyday we use way more than we can find we may have a surplus for now but we may run out sooner than some think