Answer:
Series
Explanation:
Because I listen to my science teacher
Answer:
Explanation:
in physics, the change in direction of a wave passing from one medium to another caused by its change in speed. For example, waves in deep water travel faster than in shallow.from one medium to another or from a gradual change in the medium. Refraction of light is the most commonly observed phenomenon, but other waves such as sound waves and water waves also experience refraction in other words it can be all of them or i can narrow it down some more it can have a change in dirction when light enters into a traveling point for example after moving through air it passes through a prism called compare reflection
Answer:

Explanation:
mass of object = m
Mass of planet = M
Radius of planet = R
Height = h
Let the speed of the object as it hits the earth's surface is v.
the value of acceleration due to gravity
g = G M / R^2
where, g is the universal gravitational constant.
Use third equation of motion

where, u is the initial velocity which is equal to zero.
So, 

Answer:
Weight = 4900 N
Explanation:
Given:
Mass of the piano is, 
Acceleration due to gravity is, 
Height to which the piano is raised is 8.0 m.
We are asked to determine the weight of the piano.
We know that, weight of a body is nothing but gravitational force acting on it by the center of Earth. It is equal to the product of mass and acceleration due to gravity.
Weight is independent of height til the height is very less than the radius of Earth. At very high altitudes which are comparable to the radius of Earth, the value of 'g' changes and hence the weight. But, here the height is very small and hence the value of 'g' equals 9.8 m/s² only.
Thus, weight of the piano is given as:
Weight = Mass
Acceleration due to gravity
Weight = 
Weight = 
Weight is a force so, its unit is same as that of force and hence it is measured in Newtons.
Therefore, the weight of the piano is 4900 N.
Answer:
The height from which the rock was thrown is 1.92 m
Solution:
As per the question:
Speed with which the rock is thrown, v = 12.0 m/s
Horizontal distance traveled by the rock before it hits the ground, d = 15.5 m
Launch angle, 
Now,
To calculate the height, h from which the rock was thrown:
First, since we consider the horizontal motion in the trajectory of the rock, thus the time taken is given by:


Now,
The height from which the rock was thrown is given by the kinematic eqn, acceleration in the horizontal direction is zero:

