Answer:
Convection
Explanation:
three types of heat transfer
Heat is transfered via solid material (conduction), liquids and gases (convection), and electromagnetical waves (radiation).
Answer:
Explanation:
As we know that the resistance of the wire is directly proportional to the length of wire and inversely proportional to the area of crossection of the wire.
As the material is copper for both the wires so the resistivity is same and the voltage is also same. As their resistance is different it means either length is different or the area of crossection is different.
Answer:
D
Explanation:
Cells are the smallest unit of organizaiton, followed by tissues, organs, organ systems, and then organisms themselves.
Answer:
option C
Explanation:
given,
diameter of circular room = 8 m
rotational velocity of the rider = 45 rev/min
= 
=4.712 rad/s
here in this case normal force is equal to centripetal force
N = m r ω²
N = m x 4 x 4.712²
N = 88.83m
frictional force = μ N
= 88.83m x μ
now, for the body to not to slide
gravity force is equal to frictional force
m g = 88.83 m x μ
g = 88.83 x μ
9.8 = 88.83 x μ
μ = 0.11
hence, the correct answer is option C