Answer:
Velocity (magnitude) is 98.37 m/s
Explanation:
We use the vertical component of the initial velocity, which is:

Using kinematics expression of vertical velocity (in y direction) for an accelerated motion (constant acceleration, which is gravity):

Now we need to find
as a function of
. We use the horizontal velocity, which is always the same as follow:

We know the angle at 3 seconds:

Substitute
in
and then solve for 

With this expression we go back to the kinematic equation and solve it for initial speed

Answer:
(1) A sound wave a mechanical wave because mechanical waves rely on particle interaction to transport their energy, they cannot travel through regions of space that are void of particles. Sound is a mechanical wave and cannot travel through a vacuum. These particle-to-particle, mechanical vibrations of sound conductance qualify sound waves as mechanical waves. Sound energy, or energy associated with the vibrations created by a vibrating source, requires a medium to travel, which makes sound energy a mechanical wave. The answer is(B) it travels in the medium.
(2) An ocean wave is an example of a mechanical transverse wave
The compression is the part of the compressional wave where the particles are crowded together. The rarefaction is the part of the compressional wave where the particles are spread apart. The answer is (C) Compression.
<span>An imaginary line perpendicular to a reflecting surface is called "a normal" (principle line)
So, Your Answer would be Option B
Hope this helps!</span>
The elastic potential energy stored in the stretched spring is 1 J.
<h3>What is Hooke's law?</h3>
Hooke's law states that; provided the elastic limit is not exceeded, the extension of the spring is directly proportional to the force on the spring.
Given that;
Force on the spring = 350 Newton
Distance stretched = 7 centimeters or 0.07 m
Hence;
F = ke
k = F/e = 350 Newton/0.07 m = 5000 N/m
Work done in stretching a spring = 1/2ke^2
= 0.5 × 5000 × (2 × 10^-2)^2 =1 J
Learn more about elastic potential energy: brainly.com/question/156316
Answer:
Mass and height
Explanation:
Gravitational potential energy is energy an object possesses because of its position in a gravitational field. The most common use of gravitational potential energy is for an object near the surface of the Earth where the gravitational acceleration can be assumed to be constant at about 
Which is represented as;

stands for gravitational potantial energy,
m stands for mass of object,
g is the gravitational constant and
h is the height.
Here we see that mass of object and height is directly proportional to the gravitational potential energy.
That means increasing in mass and height will result in increasing gravitational potential energy.