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a phenomenon whereby the moon appears bluish owing to smoke or dust particles in the atmosphere
Answer: the force when the catapult swings has the same force as it does when coming down
Explanation:
for every reaction there is an equal opposite reaction
Answer:
(a): I = 4.6875 A
(b): P = 562.5 W
(c): P mech = 492.1875 W
Explanation:
Data Given:
V= 120 V
E= 105 V
R= 3.2 Ω
To find:
(a): I = ?
As we know that in a DC series motor the equation to be used will be:
V = Ε + (I) (R)
120 V = 105 V + ( I ) (3.2 Ω),
I= 15/3.2
I= 4.6875 A ans
Now moving towards Power delivered i.e.
(b): P del :
P del = V X I = (120 V) (4.6875 A) = 562.5 W. ans
c) P mech = ?
The mechanical power output is the electrical power input minus the rate of dissipation of energy in the motor’s resistance (assuming that there are no other power losses):
The power P dissipated in the resistance r is
P dsptd = I²r = (4.6875 A)² X(3.2 Ω) = 70.3125 W
P mech = P del - P dsptd
P mech = 562.5 W — 70.3125 W = 492.1875 W Ans
Hope it is clear
Answer:
The right option is (d) substance undergoing a change of state
Explanation:
Latent Heat: Latent heat is the heat required to change the state of a substance without change in temperature. Latent heat is also known as hidden heat because the heat is not visible. The unit is Joules (J).
Latent heat is divided into two:
⇒ Latent Heat of fusion
⇒ Latent Heat of vaporization.
Latent Heat of fusion: This is the heat energy required to convert a substance from its solid form to its liquid form without change in temperature. E.g (Ice) When ice is heated, its temperature rise steadily until a certain temperature is reached when the solid begins to melts.
Latent Heat of vaporization: This is the heat required to change a liquid substance to vapor without a change in temperature. The latent heat depend on the mass of the liquid and the nature of the liquid. E.g When water is heated from a known temperature its boiling point (100°C) When more heat is supplied to its boiling temperature, it continue to boil without a change in temperature.
From The above, Latent heat brings about a change of state of a substance at a steady temperature.
The right option is (d) substance undergoing a change of state