b). The power depends on the RATE at which work is done.
Power = (Work or Energy) / (time)
So to calculate it, you have to know how much work is done AND how much time that takes.
In part (a), you calculated the amount of work it takes to lift the car from the ground to Point-A. But the question doesn't tell us anywhere how much time that takes. So there's NO WAY to calculate the power needed to do it.
The more power is used, the faster the car is lifted. The less power is used, the slower the car creeps up the first hill. If the people in the car have a lot of time to sit and wait, the car can be dragged from the ground up to Point-A with a very very very small power ... you could do it with a hamster on a treadmill. That would just take a long time, but it could be done if the power is small enough.
Without knowing the time, we can't calculate the power.
...
d). Kinetic energy = (1/2) · (mass) · (speed squared)
On the way up, the car stops when it reaches point-A.
On the way down, the car leaves point-A from "rest".
WHILE it's at point-A, it has <u><em>no speed</em></u>. So it has no (<em>zero</em>) kinetic energy.
This would be the definition of gravitational force, I believe. The force of attraction between 2 objects based on the mass of the objects.
Answer:
the measured charge will be -2 elementary charges.
Explanation:
Answer:
v1=21.81m/s
Explanation:
<em>When a golfer tees off, the head of her golf club, which has a mass of 160 g, is traveling 50 m/s just before it strikes a 46 g golf ball at rest on a tee. Immediately after the collision, the club head continues to travel in the same direction but at a reduced speed of 44 m/s. Neglect the mass of the club handle and determine the speed (in m/s) of the golf ball just after impact.</em>
According to the law of conservation of momentum, if the net external force on a system is zero, then the linear momentum of the system is conserved.
During collision of two particles, the external force on the system of two colliding particles is zero (only internal force acts between the colliding particles), therefore, the momentum is conserved during the collision.
Answer and Explanation:
Given :
head of the golf club=160g
velocity of the golf club=50 m/s
golf ball mass=46g
velocity=om/s
m1u1+m2u2=m1v1+m2v2.........................................1
160*50 +46*0=160*44+46*v1
8000=7040+46v1
960=46v1
v1=960/46
v1=21.81m/s
