THAT LINK IS A VIRUS NEVER GO TO A LINK and if you go to “goggle” you should see a camera icon and take a picture of the question and get the answer there
Assuming that it continues to accelerate at the same rate it will take another 10 seconds to reach 40 m/s.
Answer:
Explanation:
Since the first question states that there is a change in the velocity from rest to 20 m/s in 10 seconds time interval. So the acceleration experienced by the car during this 10 seconds should be determined first as follows:
Acceleration = (final velocity-initial velocity)/Time
Acceleration = (20-0)/10 = 2 m/s².
So this means the car is traveling with an acceleration of 2 m/s².
As it is stated that the car continues to move with same acceleration, then in the second case, the acceleration is fixed as 2 m/s², initial velocity as 20 m/s and final velocity as 40 m/s. So the time taken for the car to reach this velocity with the constant acceleration value will be as follows:
Time = Change in velocity/Acceleration
Time = (40-20)/2 = 20/2=10 s
So again in another 10 seconds by the car to reach 40 m/s from 20 m/s. Similarly the car will take a total of 20 seconds to reach from rest to 40 m/s value for velocity.
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:
m₂ = 3kg
Explanation:
The question wasn't clear about what direction the initial velocity of the second cart was, so I'll assume it was going left at 2.0m/s.
Anyway, this is a conservation of momentum problem. The equation you need to use is the one written in blue. They want you to solve for the mass of the second cart, so do some algebra and rearrange that blue equation in term of m₂.
Now that you have the equation for m₂, plug in all the values given from the question and you'll get 3kg.