We have the equation of motion
, where s is the displacement, a is the acceleration, u is the initial velocity and t is the time taken.
Here displacement = 100 m, Initial velocity = 0 m/s, acceleration = 9.81 
Substituting

A cannon ball is launched off a 100 m cliff horizontally with an initial horizontal velocity (Vx) of 50 m/s will take 4.52 seconds to reach the ground.
One is legitimate and the other is not.
Answer:
526.57 Pa
Explanation:
P ( pressure at the bottom of the container) = 1.049 × 10^5 pa
Using the formula of pressure in an open liquid
Pw ( pressure due to water) = ρhg where ρ is density of water in kg/m³, h is the height in meters, and g is acceleration due to gravity in m/s²
Pw = 1000 × 9.81 ×0.209 = 2050.29 Pa
P( atmospheric pressure) = 1.013 × 10^5 Pa
Pl ( pressure due to the liquid) = ρ(density of the liquid) × h (depth of the liquid) × g
Subtract each of the pressure from the absolute pressure at the bottom
P(bottom) - atmospheric pressure
(1.049 × 10^5) - (1.013 × 10^5) = 0.036 × 10^5 = 3600 Pa
subtract pressure due to water from the remainder
3600 - 2050.29 = 1549.71 Pa
1549.71 = ρ(density of the liquid) × h (depth of the liquid) × g
ρ (density of the liquid) = 1549.71 / (h × g) = 1549.71 / (0.3 × 9.81) =526.57 Pa
Answer:
the ray is reflected infinite number of times by 2 plane mirrors placed parallel to each other as each reflected ray would be the incident ray for the other.
Explanation:
the ray is reflected infinite number of times by 2 plane mirrors placed parallel to each other as each reflected ray would be the incident ray for the other.
Placing one mirror at an angle causes reflections to curve.
The impulse-momentum theorem