Answer:
42.6083 mi/h
Explanation:
Given: A car travels 8km in 7 minutes.
To find: Find the speed of the car.
Formula: 
Solution: Since the formula for the speed of an object (which is the car) is speed = distance ÷ time, divide the distance (8km) by the time (7min)
Speed = 42.6083 miles per hour
Positive 2n to the right of the box
Answer:
Work done= Energy transferred
Explanation:
Work is the transfer of energy. In physics we say that work is done on an object when you transfer energy to that object. If you put energy into an object, then you do work on that object (mass).
Answer:
0.31
Explanation:
horizontal force, F = 750 N
mass of crate, m = 250 kg
g = 9.8 m/s^2
The friction force becomes applied force = 750 N
According to the laws of friction,
Friction force = μ x Normal reaction of the surface
here, μ be the coefficient of friction
750 = μ x m g
750 = μ x 250 x 9.8
μ = 0.31
Thus, the coefficient of static friction is 0.31.
To determine the energy equivalent of an object, we use the famous equation of Einstein which is E=mc^2 where m is the mass of the object and c is the speed of light (3x10^8 m/s). We calculate as follows:
E = mc^2
E = 1.83 kg (3x10^8 m/s)^2
E = 1.647x10^17 J
