Motaion would be it have a good day
Friction force is equal to the applied force F until the block starts moving. Hence, it will increase until the maximum value of 3.0*10*0.50=150 N.
While it's moving, the friction will be 3.0*10*0.2 = 60 N, constant. The rest of the applied force will accelerate the block.
Answer:
25 times greater
Explanation:
Let the mass of the car is m
Initial speed, u = 20 km/h = 5.56 m/s
Final speed, v = 100 km/h = 27.78 m/s
The formula for the kinetic energy is given by
So, initial kinetic energy
Ki = 15.466 m
final kinetic energy
Kf = 385.86 m
Increase in kinetic energy is given by
=
= 385.86 / 15.466 = 25
So, the kinetic energy is 25 times greater.
You're saying that it is the same thing to add or subtract B. This means that B must be the zero vector.
This works with numbers as well, if you feel more familiar to think it this way: in general, if you add something to a number you make it bigger, whereas if you subtract it, you make it smaller.
The only way to cause adding and subtracting to be the same thing is to add or subtract zero: in both cases, you're doing nothing.