Answer:
D. Both occur between objects independently whether they are in contact or not.
Explanation:
- The gravitational force is a force that is exerted between two (or more) objects having mass. This force is always attractive and its magnitude is given by
where G is the gravitational constant, m1 and m2 are the two masses, and r is the distance between the two masses.
- The electrical force is a force that is exerted between two (or more) objects having electrical charge. It can be either attractive or repulsive, depending on the sign of the two charges, and its magnitude is given by
where k is the Coulomb's constant, q1 and q2 are the two charges, and r the distance between the two charges.
Looking at both formulas, we see that the two forces are present even when the two objects are not in contact with each other (in fact, r can assume any value in the formula). They are said to be non-contact forces. Therefore, the correct option is
D. Both occur between objects independently whether they are in contact or not.
Answer:
A. fuel mileage and longevity
Explanation:
For a person purchasing a car, car longevity is one of the main concern. They are also interested in many things such as maximum mileage and service life.
By properly monitoring and assessing few measures one can maintain the efficiency and longevity of the car. One such thing is by monitoring the liquid levels of the car. Certain liquids like the coolant or radiator water level should be well maintain in proper level in order to run the car economically.
Thus by doing this, one can optimize the car's longevity and the fuel mileage.
Hence the correct option is (A).
The weight of the box is (mass) x (gravity) = (50 kg) x (9.8m/s²) = 490 newtons.
If the box is sliding at constant speed, and not speeding up or slowing down,
that means that the horizontal forces on it add up to zero.
Since you're pushing on it with 53N in <em><u>that</u></em> direction, friction must be pulling
on it with 53N in the <u><em>other</em></u> direction.
The 53N of friction is (the weight) x (the coefficient of kinetic friction).
53N = (490N) x (coefficient).
Divide each side by 490N : Coefficient = (53N) / (490N) = 0.1082 .
Rounded to the nearest hundredth, that's <em>0.11 </em>. (choice 'd')
Answer:
A:1.94
Explanation:
cause that the only one on there
We know that the change in momentum is equals to the product of force and time that is impulse ( 
). Therefore, we need to determine the value of that the water is in air by using the second equation of motion,
Here, u is initial velocity which is zero.
.
Thus, impulse
From Newton`s second law,
Therefore, impulse
Given, 
and 
Substituting these values, we get
Change in momentum = impulse
.
