To solve the exercise it is necessary to take into account the definition of speed as a function of distance and time, and the speed of air in the sound, as well
Where,
V= Velocity
d= distance
t = time
Re-arrange the equation to find the distance we have,
d=vt
Replacing with our values
It is understood that the sound comes and goes across the entire lake therefore, the length of the lake is half the distance found, that is
Therefore the length of the lake is 634,55m
Answer:
1. 60 m/s.
2. 3600 m.
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 0
Acceleration (a) = 0.5 m/s²
Time (t) = 2 mins
Final Velocity (v) =?
Distance travelled (s) =?
1. Determination of the velocity at the end of 2 minutes.
Initial velocity (u) = 0
Acceleration (a) = 0.5 m/s²
Time (t) = 2 mins = 2 x 60 = 120 secs
Final Velocity (v) =?
v = u + at
v = 0 + (0.5 x 120)
v = 60 m/s
Therefore, the velocity at the end of 2 minutes is 60 m/s.
2. Determination of the distance travelled.
Initial velocity (u) = 0
Acceleration (a) = 0.5 m/s²
Final velocity (v) = 60 m/s
Distance travelled (s) =..?
v² = u² + 2as
60² = 0 + 2 x 0.5 x s
3600 = 1 x s
s = 3600 m
Therefore, the distance travelled is 3600 m.
Answer:
Explanation:
100 W bulb is using energy of 100 J in one second.
22 percent of the electrical energy is transformed to radiant energy.
a )
So , electrical energy is transformed to radiant energy per second
= 100 x .22 = 22 J
energy transformed in one minute = 22 x 60 J
= 1320 J
b )
electrical energy is transformed to heat energy per second
= 100 x .78 = 78 J
energy transformed in one minute = 78 x 60 J
= 4680 J
