Answer:
one billion to ten billion joules.
Explanation:
To keep a 100-watt light bulb going for one second, one hundred joules of energy will be used.
By Newton's second law, the net vertical force acting on the object is 0, so that
<em>n</em> - <em>w</em> = 0
where <em>n</em> = magnitude of the normal force of the surface pushing up on the object, and <em>w</em> = weight of the object. Hence <em>n</em> = <em>w</em> = <em>mg</em> = 196 N, where <em>m</em> = 20 kg and <em>g</em> = 9.80 m/s².
The force of static friction exerts up to 80 N on the object, since that's the minimum required force needed to get it moving, which means the coefficient of <u>static</u> friction <em>µ</em> is such that
80 N = <em>µ</em> (196 N) → <em>µ</em> = (80 N)/(196 N) ≈ 0.408
Moving at constant speed, there is a kinetic friction force of 40 N opposing the object's motion, so that the coefficient of <u>kinetic</u> friction <em>ν</em> is
40 N = <em>ν</em> (196 N) → <em>ν</em> = (40 N)/(196 N) ≈ 0.204
And so the closest answer is C.
(Note: <em>µ</em> and <em>ν</em> are the Greek letters mu and nu)
Answer:
129 J/Kg°C
Explanation:
Given :
Mass of gold, m = 1.2kg
Quantity of heat applied, Q = 3096 J
Temperature, t2 = 40°C
Temperature, t1 = 20°C
Change in temperature, dt = (40-20)°C = 20°C
Using the relation :
Q = mcdt
Where, C = specific heat capacity of gold
3096 = 1.2kg * C * 20°C
3096 J = 24kg°C * C
C = 3096 J / 24 kg°C
C = 129 J/Kg°C
Answer:
Force is classified as a push or a pull
Explanation:
