Answer:
Explanation:
Since the object is under a circular motion, according to Newton's second law, when the object is at the top of the circle we have:
Where 
is the centripetal force and is given by:
Replacing and solving for T:
Answer:19ohms
Explanation:
equivalent resistance=5+2+12
equivalent resistance=19ohms
Answer:
The force would be the same in both cases - option C.
Explanation:
The change in momentum is known as an impulse. In the two cases under consideration, the change in momentum is the same, thus impulse for both cases is the same.
Impulse is the average force multiplied by time interval.
I = F(average)*ΔT. Where F(average) is the average force and ΔT is the time interval.
The average force in both cases is the same since the collision time is the same.
Thus option C is the correct answer.
Pulling a person down so we stick to the surface
Answer:
True The net force must be zero for the acceleration to be zero
Explanation:
In order to analyze the statements of this problem we propose your solution.
First let's look at Newton's first, which stable that every object is at rest or with constant speed unless something takes it out of this state (acceleration)
Now let's look at the second postulate, which says that force is related to the product of the mass of a body and its acceleration.
As a result of these two laws, for a body is a constant velocity the summation force on it must be zero.
Now we can analyze the statements given.
True The net force must be zero for the acceleration to be zero
False. If the force is different from zero, there is acceleration that changes the speeds
False. There may be forces, but the sum of them must be zero
False. If a force acts, the acceleration is different from zero and the speed changes
