D
Because if an object is moving at a constant speed the force of friction must equal the applied (horizontal) force, and for it to be accelerating or decelerating, the force of friction and the applied force must be unequal
Answer:
d = 421.83 m
Explanation:
It is given that,
Height, h = 396.9 m
Horizontal speed, v = 46.87 m/s
We need to find the distance traveled by the ball horizontally. Let t is the time taken by the ball. Using second equation of motion for vertical direction. So,

Now d is the distance covered by the cannonball. So,

Hence, this is the required solution.
Answer:
It reveals that light is a wave
Explanation:
Diffraction is the property of a wave in which there is a bending of the wave about the corners of an obstacle or aperture into the geometrical shadow of the obstacle or aperture.
This simply implies that a wave bends or spreads out when it passes through openings. Since the light diffracts through small slits and diffraction has been shown to occur in water waves and sound waves, this property of diffraction can only be characteristic of a wave and thus, this evidence reveals that light is a wave.
Answer:
2 J
Explanation:
A charged capacitor of capacitance
with energy of 7.54 J, is connected in parallel with another capacitor
, so the charge is equally distributed between them.
(a) The energy stored in the capacitor before it being connected to the other capacitor is:

The energy stored in the electric field is the sum of the energies of the two capacitors:

since the charge equally distributed,
=
=
. and since they are connected in parallel the potential difference on both of them is the same
:

hence,
