D. lenses focus light , mirrors do not
Answer:
Friction is a force that holds back the movement of a sliding object.
Explanation:
The two types of friction: Static friction and Kinetic friction. Static friction operates between two surfaces that aren't moving relative to each other, while kinetic friction acts between objects in motion.
you can find it using the equation: potential energy=mass*gravitational acceleration*height.
energy=50kg*9.8N/kg*40m=19600Nm=19600J or 19.6kJ
Sometimes they use 10 instead of 9.8 for the g constant.
Rember to make me Brainliest!!!
This is an example of conduction
The second and third laws of thermodynamics states that absolute zero cannot be reached. The correct option among all the options that are given in the question is the third option or option "C". Both the laws actually deal with the relations that exist between heat and other forms of energy. I hope the answer helps you.