Answer:
potential enrgy U = m g L sin θ
speed V = √(2g L sin θ)
Explanation:
The expression for the gravitational potential energy of a body is
U = mg Y - mg Yo
Where Y give us a constant initial energy from which the differences are measured, for general simplicity it is selected as zero, Yo= 0
What we find an expression for height, let's use trigonometry
sin θ= Y / L
Y = l sin θ
We substitute in the power energy equation
U = m g L sin θ
2. The mechanical energy of the system is conserved, so we will write the mechanical energy at two points the highest and the lowest
Highest Em = U
Lower Em = K
U = K
m g L sin θ = ½ m v²
V = √(2g L sin θ)
Explanation:
average speed is the total distance divided by total time
Answer:
1.54 kg
Explanation:
mass of first block (m) = 0.76 kg
acceleration due to gravity (g) = 9.8 m/s
what is the mass (m) of the second block
mg = kx
where m is the mass, g is the acceleration due to gravity, k is the
spring constant and x is the extension
0.76 x 9.8 = kx
7.5 = kx
k = 7.5/x ... equation 1
- when a second block is attached to the first one the amount of stretch triples (this means that extension (x) = 3x)
therefore the new mass becomes m + 0.76 and the extension
becomes 3x
with the new mass and extension, mg = kx now becomes
(m+0.76)g = k(3x) ... equation 2
Recall that k = 7.5/x from equation 1, substituting this value of k into
equation 2 we have
(m+0.76)g =
× (3x)
(m+0.76)g = 7.5 × 3
substituting the value of g = 9.8 m/s^{2}
(m + 0.76) x 9.8 = 7.5 x 3
m + 0.76 = 22.5 ÷ 9.8
m + 0.76 = 2.3
m = 2.3 - 0.76 = 1.54 kg
So,
GPE (graviational potential energy) = mass x g x height
GPE is depends on where zero height is defined. In this situation, we define h = 0 as the initial height.



The builder has gained 18.375 kJ of PE.