Answer:
1.503 J
Explanation:
Work done in stretching a spring = 1/2ke²
W = 1/2ke²........................... Equation 1
Where W = work done, k = spring constant, e = extension.
Given: k = 26 N/m, e = (0.22+0.12), = 0.34 m.
Substitute into equation 1
W = 1/2(26)(0.34²)
W = 13(0.1156)
W = 1.503 J.
Hence the work done to stretch it an additional 0.12 m = 1.503 J
Answer: 14.28 m/s
Explanation:
Assuming the girl is spinning with <u>uniform circular motion</u>, her centripetal acceleration
is given by the following equation:
(1)
Where:
is the <u>centripetal acceleration</u>
is the<u> tangential speed</u>
is the <u>radius</u> of the circle
Isolating
from (1):
(2)
<u />
Finally:
This is the girl's tangential speed
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:
His speed in meters per second was 2. Or, 2 meters per second.
Explanation:
Answer:
3 A
Explanation:
The relationship between voltage, current and resistance in a conductor is expressed by Ohm's law, which states that:

where:
V is the potential difference across the conductor
R is the resistance of the conductor
I is the current flowing through it
In this problem, for this flashlight we have:
V = 90 V is the potential difference
is the resistance of the flashlight
Solving for I, we find the current:
