The speed of a falling object is not directly affected by mass. Air resistance is the deciding factor in the time is takes for an object to reach the ground. Two objects of different mass will accelerate at the same rate. This was discovered by Galileo. Newton's second law states that F=ma. This means that if both accelerate at the same rate, then the force acting on the objects must be different, and the greater the mass, the greater the force of gravity that is acting upon the object.
The answer would be the coulombs law.
30 minutes is 1/2 of an hour.
So if you just multiplied 21×2, you would get you answer.
The answer is:
42 kilometers per hour
No. Sadly, you're not right. The whole problem here is the meaning of a few words. "Starts out"is the same thing as "initial" conditions. "At rest" is the same thing as not moving ... zero speed. So if an object starts out at rest, that says that its initial speed is zero ... choice 'b'.
Answer:
72Watts
Explanation:
Power = Force * distance/Time
Given the following
Force = 2.4 x 10^2 = 240N
distance = 1.2m
Time = 4.0secs
Substitute
Power = 240*1.2/4
Power = 60 * 1.2
Power = 72watts
Hence the power required to lift the box is 72Watts
