Answer
Work done will be
and it will be positive
Explanation:
We have given charge 
We have to find work done in moving the charge from 15 volt to 8 volt
Let 
So potential difference 
We know that work done
, here Q is charge and V is potential difference
So work done 
It will be positive work done because work is done in moving charge from higher potential to lower potential
Explanation:
When there is no change in chemical composition of a substance then it is known as physical change.
When we say that mass is conserved during a physical change then it means that total mass of the substance or object will remain the same from beginning till the end.
For example, a metal box of mass 20 grams is beaten with hammer. Its shape will change which is a physical change and after beaten with the hammer its mass still remains 20 grams.
Answer : The de-Broglie wavelength of this electron, 
Explanation :
The formula used for kinetic energy is,
..........(1)
According to de-Broglie, the expression for wavelength is,

or,
...........(2)
Now put the equation (2) in equation (1), we get:
...........(3)
where,
= wavelength = ?
h = Planck's constant = 
m = mass of electron = 
K.E = kinetic energy = 
Now put all the given values in the above formula (3), we get:


conversion used : 
Therefore, the de-Broglie wavelength of this electron, 
Answer:
Explanation:
A wave is a phenomenon that travels through a material medium without any permanent effect on the medium. It can be classified as mechanical or electromagnetic waves. And the two major types are transverse and longitudinal.
From the given question;
1. Longitudinal waves e.g sound waves, waves in a spring'
2. Frequency (number of cycles per second).
3. Wavelength of the wave. Measured in meters.
4. Transverse waves e.g light waves, water waves.
5. Wave speed.
6. Electromagnetic waves e.g ultraviolet waves, X-rays etc.
7. Amplitude.
8. Hertz.
9. Rarefaction
10. Compression
Answer:
Hurricane watch means hurricane conditions are expected in a specified area. As defined by National Oceanic and Atmospheric Administration (NOAA), it means that hurricane conditions (sustained winds of 74 mph or greater) are possible within your area. WHILE,
Hurricane warnings means hurricane conditions are expected in an area.
So while hurricane watch may not occur, hurricane warnings will most likely occur. Watch is usually issued hours before the warning is.