Answer:
Three types of electromagnetic waves, used to transmit various information
Explanation:
A form of energy waves having both electric & magnetic fields are Electromagnetic waves. Three types -
Radio Waves - These have longest wavelengths & transmit data through radio, satellites, radar .
Micro Waves - These have shorter wavelengths & are used in cooking appliances & predicting weather.
X rays - These have more short wavelength and can penerate soft tissues like skin & muscle, hence are used for medical examining
Answer:
W = 0
Explanation:
We are given with, a construction worker is carrying a load of 40 kg over his head and is walking at a constant velocity. He travels a distance of 50 m.
The work done by an object is given by :

F = ma
So,

m is mass
a is acceleration
d is displacement
The worker is moving with constant velocity, its acceleration will be 0. So, the work done by the worker is 0.
As the <em>voltage</em> applied to a crcuit increases, the power dissipated by the circuit, and the current flowing through the circuit, both also increase.
Answer:
Bob provided the greatest impulse.
Explanation:
Given:
Arnold exerts force = 300 N for 3 seconds
Bob exerts force = 500 N for 2 seconds
Cecil exerts force = 200 N for 4 seconds.
Find:
Highest impulse
Computation:
Impulse = Force × TIme
Arnold provides impulse = 300 N × 3 seconds = 900 N/s
Bob provides impulse = 500 N × 2 seconds = 1,000 N/s
Cecil provides impulse = 200 N × 4 seconds = 800 N/s
Therefore, Bob provided the greatest impulse.
Answer:
Explanation:
Givens
Heat of Fusion = 2.05 * 10^5 J / kg watch the units.
Heat to actually melt the copper = 82 10^5 J
Formula
Mass of copper = Heat / Heat of Fusion
Solution
Mass of copper = 82*10^5 J / (2.05 * 10^5 J / kg)
Mass of copper = 40 kg
Notice that the kg is in the denominator of the second fraction. The rules of fractions would tell you the 1/1 / / 1 /kg . You take the right fraction and turn it upside down and multiply. 1 / 1 * kg/1 = 1* kg / 1*1 which is just kg.
Answer 40 kg of copper