Answer:
Explanation:
<em><u>Considering the density & specific heat capacity of coffee to be equal to that of water.</u></em>
<em><u>GIVEN:</u></em>
- density
- specific heat
- mass of coffee,
- initial temperature of coffee,
- final temperature of coffee,
- power rating of oven,
- time taken to reach the final temperature,
<u>Heat released by the coffee to come to 60°C:</u>
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<u>Now the energy used by the oven in the given time:</u>
Now the efficiency:
Answer:
A. 5.4 * 10^(-4) m
B. 500V
Explanation:
A. Electric potential, V is given as:
V = kq/r
This means that radius, r is
r = kq/V
r = (9 * 10^9 * 30 * 10^(-12))/500
r = (270 * 10^(-3))/500
r = 5.4 * 10^(-4) m
B. Now the radius is doubled and the charge is doubled,
V = (9 * 10^9 * 2 * 30 * 10^(-12))/(2 * 5.4 * 10^(-4) * 2)
V = 500V
Answer:
Vectors have both magnitude and direction
Explanation:
Vectors show how strong the force in because the bigger the arrow, the stronger the force. Also, it obviously shows direction because its an arrow.
Answer:
25.82 m/s
Explanation:
We are given;
Force exerted by baseball player; F = 100 N
Distance covered by ball; d = 0.5 m
Mass of ball; m = 0.15 kg
Now, to get the velocity at which the ball leaves his hand, we will equate the work done to the kinetic energy.
We should note that work done is a measure of the energy exerted by the baseball player.
Thus;
F × d = ½mv²
100 × 0.5 = ½ × 0.15 × v²
v² = (2 × 100 × 0.5)/0.15
v² = 666.67
v = √666.67
v = 25.82 m/s
Momentum question. This is an inelastic collision, so
m1v1+m2v2=Vf(m1+m2)
Vf=(m1v1+m2v2)/(m1+m2)=[(120kg)(0m/s)+(60kg)(2m/s)] / (120kg+60kg)
Vf=120kg m/s / 180kg
Vf=0.67m/s
0.67m/s
