Answer:
Electromagnetic waves
Explanation:
Electromagnetic waves are waves that consist of oscillating electric and magnetic fields, that oscillate perpendicularly to each other and perpendicularly to the direction of propagation of the wave (for such a reason, these waves are also called transverse waves).
Electromagnetic waves always travel in a vacuum at the same speed, called speed of light:
and they are classified into 7 different types, according to their frequency. From lowest to highest frequency, we have:
Radio waves
Microwaves
Infrared
Visible light
Ultraviolet
X-rays
Gamma rays
Therefore, gamma rays, x-rays, visible light and radio waves are all types of electromagnetic waves with different frequencies.
Answer:
630.75 j
Explanation:
from the question we have the following
total mass (m) = 54.5 kg
initial speed (Vi) = 1.4 m/s
final speed (Vf) = 6.6 m/s
frictional force (FF) = 41 N
height of slope (h) = 2.1 m
length of slope (d) = 12.4 m
acceleration due to gravity (g) = 9.8 m/s^2
work done (wd) = ?
- we can calculate the work done by the boy in pushing the chair using the law of law of conservation of energy
wd + mgh = (0.5 mVf^2) - (0.5 mVi^2) + (FF x d)
wd = (0.5 mVf^2) - (0.5 mVi^2) + (FF x d) - (mgh)
where wd = work done
m = mass
h = height
g = acceleration due to gravity
FF = frictional force
d = distance
Vf and Vi = final and initial velocity
wd = (0.5 x 54.5 x 6.9^2) - (0.5 x 54.5 x 1.4^2) + (41 x 12.4) - (54.5 X 9.8 X 2.1)
wd = 630.75 j
A large body of matter with no definite shape.
The SI unit is-kilogram(kg).
<span>Subrahmanyan Chandrasekhar
</span>
When driving on roads that may be slippery, do not make any sudden changes in speed or direction. Option D is correct.
<h3 /><h3>What is a slippery surface?</h3>
The slick road sign serves as a warning. When the road is wet or ice, drivers should use extra caution and reduce their speed. When the weather is bad, avoid making any rapid changes in direction.
When driving on roads that may be slippery, do not make any sudden changes in speed or direction. It may cause accident because the vehicle can lose their balance.
Hence, option D is correct.
To learn more about the slippery surface, refer to the link;
brainly.com/question/1953680
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