Answer:
The work done by gravity is 784 J.
Explanation:
Given:
Mass of the block is, 
Height to which it is raised is, 
Acceleration due to gravity is, 
Now, work done by gravity is equal to the product of force of gravity and the distance moved in the direction of gravity. So,
Force of gravity is given as the product of mass and acceleration due to gravity.
. Now,
Therefore, the work done by gravity is 784 J.
A) Pitch depends on the frequency of a sound wave. The higher the pitch, the higher the frequency and the lower the pitch, the lower the frequency. Sound waves have different pitches due to varying frequency levels.
B) Sound is created as the pen vibrates. This vibrations also interacts with the air atoms and molecules, causing them to vibrate too, therefore, creating sound waves. The reason the brain grows annoyed at this continual sound is because the brain will focus on this sound only, causing the brain to go into overdrive, creating annoyance.
C) Sound waves are travelling vibrations of particles. Space does not have any atoms or particles for the sound vibrations to interact with, therefore creating zero sound waves to travel.
Hope this helps!! :))
Nuclear fusion reactions convert protons into helium; thus, becoming the source of all energy radiated by the sun.
Answer: Option D
<u>Explanation:</u>
Nuclear fusion reaction is one among the two nuclear reactions in which the atoms nucleus interact with each other to produce the products. In nuclear fusion, two smaller atoms react together to form a new atom with bigger size.
So large amount of energy is required to start the nuclear fusion reaction. The fusion reactions mostly occurs in stars. The illumination in Stars even the Sun is due to nuclear fusion reaction occurring with the atoms present in them.
Mostly the energy radiated by Sun is due to the protons-protons chain reaction. In this chain reaction, the protons get converted into helium due to nuclear fusion reaction, thus becoming the source of all energy radiated by the Sun.
To develop this problem it will be necessary to apply the concepts related to the frequency of a spring mass system, for which it is necessary that its mathematical function is described as
Here,
k = Spring constant
m = Mass
Our values are given as,
Rearranging to find the spring constant we have that,
Therefore the spring constant is 1.38N/m
Answer: When electricity flows through it.
Explanation:
The electromagnet exhibits magnetic properties only as soon as current flows through the nucleus. Namely, the electric current in the space around the electrical conductor through which it passes creates a magnetic field. Unlike a permanent magnet, which has a permanent property of magnetism, the electromagnet is a temporary magnet because the magnetic field also disappears when the current ceases.
