Answer:
1.5 hr
16.7
Explanation:
Zero apparent weight means there's no normal force.
Sum the forces in the centripetal direction.
∑F = ma
mg = mv²/r
v = √(gr)
v = √(7.4×10⁶ m × 10 m/s²)
v = 8602 m/s
The circumference of the equator is:
C = 2πr
C = 2π (7.4×10⁶ m)
C = 4.65×10⁷ m
So the period is:
T = C / v
T = (4.65×10⁷ m) / (8602 m/s)
T = 5405 s
T = 1.5 hr
The initial speed is:
v = C / T
v = (4.65×10⁷ m) / (25 h × 3600 s/h)
v = 517 m/s
The speed increases by a factor of:
8602 m/s / 517 m/s
16.7
Answer:
m = 4.44 [g]
Explanation:
This is a problem related to heat transfer and thermodynamics. The second law of thermodynamics tells us that heat goes in only one direction, from the highest temperature substance to the lowest temperature. In this case the heat goes from tea to ice. The heat transfer process could be defined as the heat rejection of one body will be equal to the Heat received by another body.
Where:
m = mass = 177[g] = 0.177[kg]
Cp = specific heat = 4186 [J/kg*C]
T_f = 29.1 [°C]
Ti = 31.1 [°C]
Q = 0.177*4186*(29.1 - 31.1)
Q = - 1481.8 [J]
Note: The negative sign means that the heat is rejected.
Recall that the heat rejected is equal to the heat transferred
As the ice is going through a phase change, the fusion latent heat should be used, i.e. when it passes from solid to liquid. The heat transfer for this process is calculated with the following expression.
Qin = m *hf
m = mass of the ice [kg]
hf = Fusion latent heat = 333700 [J/kg]
1481.8 = m * 333700
m = 0.00444 [kg] = 4.44 [g]
Answer:
11760J
Explanation:
Given parameters:
Height of hill = 30m
Weight = 40kg
Unknown:
Gravitational potential energy = ?
Solution:
To find the gravitational potential energy, it is the energy due to the position of a body;
G.PE = mgh
m is the mass
g is the acceleration due to gravity
h is the height
Now insert the parameters and solve;
G.PE = 40 x 9.8 x 30 = 11760J
Mass and velocity of course
The amount of work done by Pravat if he exerts a force of 30 N to lift a bag of groceries 0.5m is 15J.
<h3>WORK DONE:</h3>
The work done by a body can be calculated by multiplying the force exerted by the distance moved. That is;
Work done = force (F) × distance (m)
According to this question, Pravat exerts a force of 30N to lift a bag of groceries 0.5 m. The work done is calculated as follows:
Work done = 30N × 0.5m
Work done = 15J
Therefore, the amount of work done by Pravat if he exerts a force of 30 N to lift a bag of groceries 0.5m is 15J.
Learn more about work done at: brainly.com/question/8119756?referrer=searchResults
