Look at the rock sitting on the hill in the picture above. Gravity should make the rock slide down the hill. What force is acting to balance gravity,keeping the rock in place? - D. friction
Centripetal force and momentum have to do with movement. Gravity cannot balance gravity.
Answer:
1524 nm.
Explanation:
Angular separation of n th minima is given by the expression
Sin θ = n λ / a
Where λ is wavelength of light used and a is separation between two slits .
a = n λ / sin θ
For a to be minimum, sinθ has to be maximum .
maximum value of sin of any angle is 1 .
so the relation becomes as follows
a = n λ
n = 2 , λ = 762 nm.
a = 2 x 762 nm
= 1524 nm.
F=mass x acceleration = ma= 0.8*20 = 16N
Answer:
4.6 
Explanation:
Since the table is frictionless, there is no force of dynamic friction between table an block when the horizontal force is applied to it on Earth. Exactly the same is true when the table is taken to the Moon. Therefore, the Net Force acting on the object in both cases when the object accelerates, is the external horizontal force.
Notice that on Earth and on the Moon, the weight of the object (vertical and pointing up) is compensated by the normal force of the table on the object (pointing up and of the same magnitude as the weight) that precludes movement in the vertical direction. So in both cases, its acceleration will only be due to the horizontal force.
We use the equation for Net Force to find the mass of the object:

We use this mass (since the mass of the object is a constant independent of where the object is) to find the acceleration the object will experience when the 20 N horizontal force is applied on it on the Moon:

A proton repelling another proton
Like charges of the protons would repel one another.