Answer:
During a typical school day all forms of eneergy is being utilised and also transfer of energy takes place from one form to another.
Explanation:
Chemical energy- A bunsen burner burning a beaker filled with water.
Heat energy- The water in the beaker absorbing the heat from the burner.
Electrical energy- Running Fans and lights in a classroom by switches.
Solar energy- Solar energy harnessed by solar panels to run the fans and lights by converting it into electrical energy.
Potential energy- A ball being held by a student at a certain height possesses energy due to gravity.
Kinetic energy- The same ball being left by the boy from a certain height produces kinetic energy
A transmitter “encodes” or modulates messages by varying the amplitude or frequency of the wave – a bit like Morse code. At the other, a receiver tuned to the same wavelength picks up the signal and 'decodes' it back to the desired form
I think it’s A or D
Answer:
When an electric field exists in a conductor a current will flow.
This implies a voltage difference between two points on the conductor.
Electrostatics pertains to static charge distributions.
That means that an object such as a charged spherical conductor will be at the same potential (voltage) on both its outer and inner surfaces.
Using the principle of floatation.
u = w............(a)
Upthrust of fluid is equal to the weight of the object.
Let the volume of the wood be V.
The upthrust u, is related to the volume submerged in water, and that is 1/5 of it volume, that is (1/5)V = 0.2V
Formula for upthrust, u = vdg
where v = volume of fluid displaced
d = density of fluid
g = acceleration due to gravity
weight, w = mg
where m = mass
g = acceleration due to gravity
From (a)
u = w
vdg = mg Cancel out g
vd = m
The v is equal to 0.2V, which is the submerged volume. Notice that the small letter v is volume of fluid displaced, and capital V is the volume of the solid.
d is density of fluid which is water in this case, 1000 kg/m³
0.2V * 1000 = m
200V = m
Hence the mass of the object is 200V kg.
But Density of solid = Mass of solid / Volume of solid
= 200V / V
= 200 kg/m³
Density of solid = 200 kg/m³
Answer : 6.022• 10^23 atoms of potassium
