Answer:
18.6 m/s
Explanation:
= Initial height of the balloon = 11 m
= initial speed of the ball
= initial vertical speed of the ball = 7 m/s
= initial horizontal speed of the ball = 9 m/s
initial speed of the ball is given as
= final speed of the ball as it strikes the ground
= mass of the ball
Using conservation of energy
Final kinetic energy before striking the ground = Initial potential energy + Initial kinetic energy
Answer:
I. light house 1 will be warmer during the day ii. light house 2 will be warmer at night.
Explanation:
Because the land conducts heat better than water the light house farthest away from the water will get hotter during as the ground will heat up faster than the water. But this also means that the ground will lose heat faster at night where the water won't making the light house closest to the water hotter at night.
Answer:
36 Ω
Explanation:
Since the 3 resistors are connected in parallel.
The combined resistance of the resistor is
1/Rc = 1/R + 1/R + 1/R ...................... Equation 1
Where Rc = combined resistance of the three resistor, R1 = Resistance of each of the resistor
Rc = R/3 ....................... Equation 2
The formula of power is given as
P = V²/Rc
Rc = V²/P ................ Equation 3
Where V = Voltage, R = Combined Resistance, P = power.
Given: V = 48 V, 192 W.
Substitute into equation 3
Rc = 48²/192
Rc = 12 Ω
From equation 2
Rc = R/3
R = 3Rc
Where Rc = 12 Ω
R = 3×12
R = 36 Ω
Hence the resistance on each resistor = 36 Ω
Answer:
Explanation:
Amount of heat required can be found from the following relation
Q = mcΔT
m is mass of the body , c is specific heat and ΔTis rise in temperature .
Here m = 300 kg
c = 3350 J /kg k
ΔT = 30 - 25
= 5 °C
Putting the values in the expression above
Q = 300 x 3350 x 5
= 5025000 J
Rate at which energy is absorbed = 1200 J /s
Time required
= 5025000 / 1200
= 4187.5 S
= 69.8 minute
= 1 hour 9.8 mimutes.
