Answer:
Efficiency = 52%
Explanation:
Given:
First stage
heat absorbed, Q₁ at temperature T₁ = 500 K
Heat released, Q₂ at temperature T₂ = 430 K
and the work done is W₁
Second stage
Heat released, Q₂ at temperature T₂ = 430 K
Heat released, Q₃ at temperature T₃ = 240 K
and the work done is W₂
Total work done, W = W₁ + W₂
Now,
The efficiency is given as:

or
Work done = change in heat
thus,
W₁ = Q₁ - Q₂
W₂ = Q₂ - Q₃
Thus,

or

or

also,

or

thus,

thus,

or

or
Efficiency = 52%
It means that the soccer ball is a soccer ball bc it’s a soccer ball yk ?
Answer:
6.8 m/s2
Explanation:
Let g = 9.8 m/s2. The total weight of both the rope and the mouse-robot is
W = Mg + mg = 1*9.8 + 2*9.8 = 29.4 N
For the rope to fails, the robot must act a force on the rope with an additional magnitude of 43 - 29.4 = 13.6 N. This force is generated by the robot itself when it's pulling itself up at an acceleration of
a = F/m = 13.6 / 2 = 6.8 m/s2
So the minimum magnitude of the acceleration would be 6.8 m/s2 for the rope to fail
Answer: initially the packet was ascending up with the balloon.
Taking upward as positive direction;
initial velocity, u = 4.9 m/s
final velocity = v m/s
initial height, h₁ = 245 m
final height, h₂ = 0
a = -9.8 m/s²
time taken = t seconds
s = ut + 0.5at²
⇒ (h₂-h₁) = ut + 0.5at²
⇒ 0-245 = 4.9t + 0.5×(-9.8)×t²
⇒ -245 = 4.9t - 4.9t²
⇒ 4.9t² -4.9t -245 =0
Solving it, we get t = 7.59s
v = u + at = 4.9 -9.8×7.59 = 4.9 - 74.38 = -69.48 m/s
So velocity is 69.48 m/s downward
Explanation: