<span>No, there is no control group because each group is treated under test conditions.</span>
Answer:
1) A downward force of magnitude 5 N is exerted on the book by the force of of gravity
2) An upward force of magnitude 5 N is exerted on the book by the table
Explanation:
First of all, any object near the Earth's surface experiences the forces of gravity, which is also called weight of the object. This force always acts downward.
For the book in the problem, the magnitude of the weight is 5 N.
We also know that the book is at rest: this means that the net force acting on it is zero, and there must be another force balancing the weight, in order to give a zero net force. This other force is the reaction force exerted by the table on the book: the magnitude of this force must be equal to the force of gravity (so, 5 N) and its direction is opposite to the weight, therefore upward.
Answer:
The net torque about the pivot is and the answer is 'c'
c. 
Explanation:
The torque is the force apply in a distance so it is the moment so depends on the way to be put it the signs so:
Now to find the net Torque is the summation of both torques
18 electrons because protons minus the atomic mass so it would be 35-17 which gives you 18.
Answer:
Force the floor exerts on the passenger is 833 N.
Explanation:
- Weight of passenger (
) = mg = 85 × 9.8 N = 833 N
- Force the floor exerts on the passenger (
) = ?
- For the elevator with the speed as 2.0 m/s the net force is zero, it means that the force is balanced.
i.e. = - = -mg = 833 N
hence is 833 N
- If the lift was not at a constant speed i.e. if it had acceleration (
) then the case would be different.
