Given :
Mass of water, m = 2 grams.
The temperature of water drops from 31 °C to 29 °C .
The specific heat of water is 4.184 J/(g • °C).
To Find :
Amount of heat lost in this process.
Solution :
We know, heat lost is given by :
Therefore, amount of heat lost in this process is 16.736 J.
Answer:
A charge of -5.02 nC is uniformly distributed on a thin square sheet of nonconducting material of edge length 21.8 cm. "What is the surface charge density of the sheet"?
Explanation:
Surface charge density is a measure of how much electric charge is accumulated over a surface. It can be calculated as the charge per unit area.
We will convert all parameters in SI units.
Charge = Q = -5.02nC
Q = -5.02×C
As it is clear from question that Sheet is a square (All sides will be of equal length)
Area = A = (21.8×m) (21.8×
m) = 4.75×
m²
A = 4.75×m²
Surface charge density = Q/A
Surface charge density = (-5.02×C)/(4.75×
m²)
Surface charge density = -1.057× C
The tennis ball lands at a point 40.4 m from the base of the building.
The tennis ball is projected with a horizontal velocity <em>u</em> from a window, which is at a height <em>y</em> from the ground. The ball lands at a distance <em>x</em> from the base of the building. Let the ball take a time <em>t</em> to reach the ground. In the time <em>t</em> ,the ball falls a vertical distance <em>y</em> and also travel a horizontal distance <em>x</em>.
The initial vertical velocity of the ball is zero, since the ball is projected in the horizontal direction. The ball falls down under the action of gravitational force.
Thus, use the equation of motion,
rewrite the expression for <em>t</em> and calculate the value of <em>t</em> using 9.81 m/s²for <em>g</em> and 500 m for <em>y</em>.
The horizontal distance <em>x</em> is traveled using the constant velocity <em>u </em>since no force acts on the ball in the horizontal direction.
Therefore,
Substitute 4 m/s for <em>u</em> and 10.096 s for <em>t</em>
Thus, the ball lands at a point 40.4 m from the base of the building.