Because of the change in voltage.
Answer:
The combined velocity of the girl and the platform after the jump is 1.14 m/s.
Explanation:
From the law of conservation of momentum:
m1u1 = (m1 + m2)v
m1 is mass of the girl = 39 kg
m2 is mass of the hanging platform = 125 kg
u1 is initial speed of the girl = 4.8 m/s
v is combined velocity of the girl and the platform after the jump
v = m1u1/(m1+m2) = 39×4.8/(39+125) = 187.2/164 = 1.14 m/s
Answer:
400 N
Explanation:
From the question,
F = kmm'/r²........................ Equation 1
Where F = gravitation force, m and m' = mass 1 and mass 2 respectively, r = distance between the masses.
Given; F = 800 N
Substitute these values into equation 1
800 = kmm'/r².............. Equation 2
If the distance is doubled (2r), and one of the mass is doubled (2m), The new force is
F' = k(2m)(m')/(2r)²
F' = 2kmm'/4r²
F' = kmm'/2r²................. Equation 3
Comparing equation 2 and equation 3
F' = F/2............................ Equation 4
Substitute the value of F into equation 4
F' = 800/2
F' = 400 N
Answer:
And for this case we can write this expression like this:
The velocity would be given by the first derivate and we got:
And the maximum velocity would be:
Explanation:
For this case we have the following function for the position:
And for this case we can write this expression like this:
The velocity would be given by the first derivate and we got:
And the maximum velocity would be:
Answer:
T_ww = 43,23°C
Explanation:
To solve this question, we use energy balance and we state that the energy that enters the systems equals the energy that leaves the system plus losses. Mathematically, we will have that:
E_in=E_out+E_loss
The energy associated to a current of fluid can be defined as:
E=m*C_p*T_f
So, applying the energy balance to the system described:
m_CW*C_p*T_CW+m_HW*C_p*T_HW=m_WW*C_p*T_WW+E_loss
Replacing the values given on the statement, we have:
1.0 kg/s*4,18 kJ/(kg°C)*25°C+0.8 kg/s*4,18 kJ/(kg°C)*75°C=1.8 kg/s*4,18 kJ/(kg°C)*T_WW+30 kJ/s
Solving for the temperature Tww, we have:
(1.0 kg/s*4,18 kJ/(kg°C)*25°C+0.8 kg/s*4,18 kJ/(kg°C)*75°C-30 kJ/s)/(1.8 kg/s*4,18 kJ/(kg°C))=T_WW
T_WW=43,23 °C
Have a nice day! :D