In most cases the temperature must increase for thermal expansion to occur. Most substances expand as temperature increases because the atoms or molecules vibrate faster as temperature increases and experience greater separation.
Answer:
B.
Explanation:
The batteries make it so the chemical energy is being passed into the flashlight allowing it to work as designed forming light.
Explanation:
Young' modulus is the ratio of normal stress to the longitudinal strain. Mathematically, it is given by :
Normal stress is given by force per unit area. Longitudinal strain is the change in length per unit original length.
The mathematical definition of Young's modulus is given by :
..........(1)
Where
is the change in length
F is the force
A is the area of cross section
So, the Young's modulus refers to the change in length of the object. Hence, the correct option is (b) "length".
Power (watts) = work done (joules) ÷ time (seconds)
power (watts) = 1000J ÷ 20s
power (watts) = 50w
The magnet is at a gravitational force while the paper clip is at an applied force