Hello!
I'm unfamiliar with the book you are reading,
However, based on textual evidence, I think your answer relies somewhere in answer choice A or D.
I hope this helps!
Formula for potential energy is V=mgh, where m is mass in KG, g is earth acceleration (10 m/s^2), and h its height in meters. We know mass, acceleration is constant and also known, we know height also. Lets substitute
V=75*10*300=225000[J]=225[kJ] - its the answer
From a to b speed is 600+40 = 640
from b to a speed is 600-40 = 560
let t be the number of hours of flight. This would mean it would have traveled a distance of 640 miles and the distance yet to travel is 2400-640t
Time left will be (2400-640t)/640. But if they were to return to a it would fly 640t miles at 560mph which will take (640t/560) hrs
(2400-640t) / 640 = 640t / 560
560(2400 - 640t) = 640t x 640
t = 1.75hrs
Answer:
<h2>21 N</h2>
Explanation:
The force acting on an object given it's mass and acceleration can be found by using the formula
force = mass × acceleration
From the question we have
force = 3.5 × 6
We have the final answer as
<h3>21 N</h3>
Hope this helps you
Given parameters:
Mass of object = 6.7kg
Velocity = 8m/s
Unknown parameter:
Kinetic energy = ?
Energy is defined as the ability to do work. There are two forms of energy;
Kinetic and potential energy.
Kinetic energy is the energy due to the motion of a body. Whereas, potential energy is the energy due to the position of a body usually at rest.
Kinetic energy is mathematically expressed as;
Kinetic energy = 
where m is the mass of the body
v is the velocity of the body
Since we have been given both mass and velocity, input the parameter to solve for the unknown;
Kinetic energy = 
x 6.7 x 8² = 214.4J
So the kinetic energy of the body is 214.4J
