The contrast between total internal reflection and refraction is that total internal reflection is the full underwater build with no defeat of brightness, whereas refraction is the shift in the path of a tide that is parting from one medium to another.
Ohm's law states that the electrical current (I) flowing in an circuit is proportional to the voltage (V) and inversely proportional to the resistance (R). Therefore, if the voltage is increased, the current will increase provided the resistance of the circuit does not change.
Answer:The correct options are:
1. A system is a group of objects analyzed as one unit.
2. Energy that moves across system boundaries is conserved.
Explanation:
A system is defined as group of interrelated or interacting items existing as a single unit or a whole to achieve a specific objective.Energy lost by the system is equal to the energy gained by the surroundings.
Two statements are true about a system:
- A system is a group of objects analyzed as one unit.
- Energy that moves across system boundaries is conserved.
Answer:
Coefficient of friction is 
.
Work done is 
.
Explanation:
Given:
Mass of the box (
): 
kg
Force needed (
): 
N
The formula to calculate the coefficient of friction between the floor and the box is given by
Here, 
is the coefficient of friction and 
is the acceleration due to gravity.
Substitute N for , kg for and 
m/s² for into equation (1) and solve to calculate the value of the coefficient of friction.
The formula to calculate the work done in overcoming the friction is given by
Here, 
is the work done and 
is the distance travelled.
Substitute N for and 
for into equation (2) to calculate the work done.
