Answer:
Explanation:
There are 3 main forces at work here, gravity, normal and friction. The gravity pulls the car straight down and is what keeps the car on the ground. Normal force is straight up from the points where the car is touching, so since the wheels are the only parts of the car touching the street, this is where all the normal force is. Friction force opposes any and all motion, the car wants to slide down the hill and would slide down the hill if there was no friction, so the friction force is in the opposite direction of the cars intended motion.
Answer: 50 km, 0, 27.78 m/s
Explanation:
Given
Circumference of the track is 
Speed of car is 
Car drives for 
(a)Distance traveled is

(b)displacement of the car
It can be observed that 12.5 is a multiple of 50, that is, 50 km can be interpreted as 4 complete rounds of the track.
Therefore, the displacement of the car is zero.
(c)To convert kmph to m/s, multiply the entity by 

The electrostatic energy stored in a capacitor with capacitance

, with a voltage difference V applied to it, and without dielectric, is given by

Now let's assume we fill the space between the two plates of the capacitor with a dielectric with constant k. The new capacitance of the capacitor is

So, the energy stored now is

Therefore, the ratio between the energies stored in the capacitor before and after the introduction of the dielectric is
Answer:v=0.4 m/s
Explanation:
Mass hockey player 
mass of cup 
Velocity of cup 
let v be the velocity of the combined system
Conserving momentum




Answer:
Mechanical advantage=4
Explanation:
Load=1000N
Effort=250N
mechanical advantage=load/effort
Mechanical advantage=1000/250
Mechanical advantage=4