Answer:
7.24 Ω
Explanation:
Power = energy / time = 195 J / 9.81 = 19.88 W
and power = V² / R
R resistance = 12 V² / 19.88 W = 7.24 Ω
Answer:
Acceleration of the car will be 
Explanation:
We have given that car starts from rest so initial velocity of the car u = 0 m/sec
And car traveled 400 m in 10 sec
So distance traveled by car s = 400 m
Time taken to compete this distance t = 10 sec
We have to find the acceleration of the car
From second equation of motion we know that 
So 
So acceleration of the car will be
Answer:
True
Explanation:
Atoms of the same element will always have the same atomic mass or the mass listed in the periodic table.
Physical changes are those which do not affect the chemical properties of a substance. For example, when a paper is cut, the two pieces obtained are still paper. The chemical properties have not changed. Only, physically when one piece is cut to two. A chemical change occurs when the chemical properties change and a new substance with different chemical properties is obtained. For example, when the paper is burnt, it turns to ashes. Hence, this is a chemical change.
When a substance undergoes a physical change, the physical properties of the substance changes like the state (solid to liquid during melting), shape, size, volume etc. Many physical changes are reversible whereas, in general many chemical changes are irreversible.
