B. The sound of the engine will get louder and the pitch higher.
Answer:
(a) W=1.20×10⁴J
(b) U= -5.46×10⁴J
(c) Q= -4.26×10⁴J
Explanation:
Given that student does 1.20×10⁴J work
(a) W=1.20×10⁴J
Work done by student,so positive sign
During the process, his internal energy decreases by 5.46×10⁴J.
(b) U= -5.46×10⁴J.
As the Energy decreases therefore negative sign
For (c) Q
We know the formula

Answer:
The plane would need to travel at least
(
.)
The
runway should be sufficient.
Explanation:
Convert unit of the the take-off velocity of this plane to
:
.
Initial velocity of the plane:
.
Take-off velocity of the plane
.
Let
denote the distance that the plane travelled along the runway. Since acceleration is constant but unknown, make use of the SUVAT equation
.
Notice that this equation does not require the value of acceleration. Rather, this equation make use of the fact that the distance travelled (under constant acceleration) is equal to duration
times average velocity
.
The distance that the plane need to cover would be:
.