Complete Question
The complete question is shown on the first uploaded image
Answer:
The value is
Explanation:
From the question we are told that
The mass of the block is
The initial speed of the block before entering the rough section is
The time taken is t = 0.5 s
The speed with which the block leaves the rough section is
Generally from kinematic equation
=>
=>
=>
Generally the magnitude of the average frictional force is mathematically represented as
=>
=>
The negative sign show that the force is acting in the opposite direction to the direction of motion of the block
Explanation:
the unknown resistance is 9ohm
Answer:
False
Explanation:
This statement is negates the photoelectric effect.
When an electron absorbs energy it jumps from a lower shell to a higher shell. When the electron releases energy it jumps from a higher shell to a lower shell.
The Kinetic energy of an ejected electron is
Where,
h = Planck's Constant
f = Frequency of incident photon
= Work function
So, this statement is false.
Answer:
See explanations below
Explanation:
Power = Workdone/Time
Power of washer = 450watts
Time used to clean the clothes = 1hour = 3600secs
Energy used to clean a load of clothes in 1 hour of
washing = 450/3600
Energy used to clean a load of clothes in 1 hour of
washing = 0.125Joules
For drying;
Energy = 3000/1.5*3600
Energy = 3000/5400
Energy = 0.556Joules
Hence the energy in washing id 0.556Joules
a mechanical wave is a wave that is an oscillation of matter, and therefore transfers energy through a medium. while waves can move over long distances, the movement of medium transmission-the material- is limited. again, the oscillating material does not move far away from its initial equilibrium position ;)