Answer:
+16 J
Explanation:
We can solve the problem by using the 1st law of thermodynamics:
where
is the change of the internal energy of the system
Q is the heat (positive if supplied to the system, negative if dissipated by the system)
W is the work done (positive if done by the system, negative if done by the surroundings on the system)
In this case we have:
Q = -12 J is the heat dissipated by the system
W = -28 J is the work done ON the system
Substituting into the equation, we find the change in internal energy of the system:
Answer:C.The tube should be held vertically, perpendicular to the ground.
Explanation: Power lines are mainly overhead power installation that transfer electric energy from one place to another. Electric power lines contains both Magnetic field and Electric field.
Potential difference is the change in the amount of energy carried by an electric circuit from one point to another. TO MAXIMIZE THE POTENTIAL DIFFERENCE BETWEEN ONE END OF THE TUBE AND ANOTHER? THE TUBE SHOULD BE HELD VERTICALLY,PERPENDICULAR TO THE GROUND.
Resistance is the ratio of
(voltage between two points in the circuit)
divided by
(current between the same points).
It's expressed in units of Ohms, so the correct choice is "none of the above".
Answer:
The speed of the cyclist is 2.75 km/min.
Explanation:
Given
To determine
We need to find the speed of a cyclist.
In order to determine the speed of a cyclist, all we need to do is to divide the distance covered by a cyclist by the time taken to cover the distance.
Using the formula involving speed, time, and distance
where
substitute d = 88, and t = 32 in the formula
Cancel the common factor 8
km/min
Therefore, the speed of the cyclist is 2.75 km/min.
Answer:
<em>U = 66,150 J</em>
Explanation:
<u>Gravitational Potential Energy</u>
Gravitational potential energy is the energy stored in an object because of its vertical position or height in a gravitational field.
It can be calculated with the equation:
U=m.g.h
Where m is the mass of the object, h is the height with respect to a fixed reference, and g is the acceleration of gravity or 
.
The child of mass m=45 Kg is perched above a h=150 m ravine. His gravitational potential energy is:
U = 66,150 J
