Answer:
B
Explanation:
In a solution, one part has to dissolve into the other.
Electromagnetic waves about the size of a golf ball are used for
microwave radio communication and radar every day.
Electromagnetic waves that are about 4-1/2 inches long are used
in the microwave oven to heat leftover meatloaf and make popcorn .
Electromagnetic waves that are 10 times the size of an atom
are hard hard X-rays.
Electromagnetic waves that are the size of Earth's diameter
are used for ELF communications, including standard time
signals, and submarine communication.
Mechanical waves that are the same order of magnitude as
the Earth are seismic (earthquake) waves.
Gamma rays are electromagnetic waves with wavelengths in the
neighborhood of the same size as the atomic nucleus. To get
some idea of their frequency, just contemplate how long it would
take light ... (which can get to the moon in a couple of seconds) ...
to move from one side of an atomic nucleus to the other side.
Answer:
The long jumper hits the ground with a velocity of 158.54 ft/s at and angle of 30° from the horizontal.
Explanation:
This is a an example of projectile motion.
It should first be stated that the effects of air resistance and friction are negligible, so horizontal velocity does not change over the course of the jump.
To solve this problem, let's first express the x and y velocity of the jumper as components of the initial velocity and angle:
= V*Cos(30°)
= V*Sin(30°)
The distance traveled by the athlete is 26 feet, so we have:
Distance = Speed * time
26 = V*Cos(30) * time -Equation (1)
We can also make an equation for the y velocity as follows:
here a = -32.2 ft/s^2
s = 0 ft
and =V*Sin(30°)
so we get:
-Equation (2)
Solving equations 1 and 2 simultaneously we get:
V = 158.54 ft/s
t = 0.1894 s
The direction of landing remains the same as the direction of the initial jump (30° from the horizontal). This is because the height is the same, and horizontal velocity remains constant with vertical velocity being exactly the same negative value as that from liftoff.
A beam of laser is directed at a reflecting surface put on the moon when the beam of laser is reflected a receiver on the each measure the time since the beam was sent till it was received. Laser is simply light so it has constant velocity in vacuum ~ air (c = 3 x 10^8 m/s)
to find the distance:
t : time measured between launching the beam and receiving it
d : distance
d = ct