Answer:
A. The horizontal velocity vector points to the right & equals v cos θ.
Explanation:
The motion describes a parabolic path, where the horizontal speed is constant and the horizontal velocity vector always points to the right and equals v*cos θ.
Answer:
Refractive index of film = 1.27
Explanation:
for the constructive interference of reflected light we know that the condition is given as

here we know
= refractive index of the liquid film
t = thickness of layer
t = 246 nm

now from the above condition of maximum interference


Answer:

Explanation:
We know force between 2 charges is given by

It is given initial force is attractive of magnitude
Let
be the initial separation
Thus

Now
Let
be the final separation
Thus final force becomes

It is given
=
...................(i)
Using values of
and
in equation i we have
= 
thus

Thus the final separation is one-fourth of the initial separation
Answer:
khoảng cách = 8km / h
Explanation:
khoảng cách = tốc độ / thời gian
khoảng cách = 12/40
khoảng cách = 8km / h