Answer:
Speed of the ball relative to the boys: 25 km/h
Speed of the ball relative to a stationary observer: 35 km/h
Explanation:
The RV is travelling at a velocity of
Here we have taken the direction of motion of the RV as positive direction.
The boy sitting near the driver throws the ball back with speed of 25 km/h, so the velocity of the ball in the reference frame of the RV is
with negative sign since it is travelling in the opposite direction relative to the RV. Therefore, this is the velocity measured by every observer in the reference frame of the RV: so the speed measured by the boys is
v = 25 km/h
Instead, a stationary observer outside the RV measures a velocity of the ball given by the algebraic sum of the two velocities:
v = +60 km/h + (-25 km/h) = +35 km/h
So, he/she measures a speed of 35 km/h.
The wave length becomes shorter and the pitch becomes higher
<span>Question: How much power does an electric device use if the current is 36.0 amps and the resistance is 3.9 ohms? </span>
How?:
Equation: P = I^2 R
Meanings:
P = Power in Watts
I = Current in Ampere
R = Resistance in ohms.
Plugged in: P = 36^2<span> x 3.9 = 5054.4
Answer: P= </span>5100 watts.
HOPE THIS HELPS! ^_^
<span> </span>
Answer:
Thus, the time for the first lamp is 44 minutes.
Explanation:
Power of first lamp, P' = 1000 W
Power of second lamp, P'' = 4400 W
time for second lamp, t'' = 10 minutes
Let the time for first lamp is t'.
As the energy is same, so,
P' x t' = P'' x t''
1000 x t' = 4400 x 10
t' = 44 minutes
Explanation:
identified by one of the Chi Omega survivors as the assailant, and hair and fiber evidence tied him to the Leach murder. His trial for the Florida attacks in June 1979 was the first-ever nationally televised trial in the United States.