Answer: commander in chief of the armed forces
Explanation: as the president of the United state, president Bush has the power of the commander in chief of the armed forces of the United States. This give him power to issue command to the armed forces.
Answer:
-15m/s/s
Explanation:
Acceleration = change in speed/ change in time
The change in speed is calculated by subtracting the initial speed from the final speed, so the change in speed is: 50 - 80 = -30m/s. The change in time is 2 - 0 = 2.
So the car acceleration is -30/2 = -15m/s/s
It is negative because it is decelerating.
Hope this helped!
- mechanical energy is conserved in all the listed situations
- true
- potential energy
- 490 J
- 750,000 J
EXPLANATION
1. sum of kinetic energy (KE) and potential energy (PE) is known as mechanical energy
- kinetic energy is the motion of an object
- potential energy is the position of an object
there is kinetic energy and other energies in the listed situation.
2. since the height decreases due to the fall, the potential energy also decreases but the speed increases and kinetic energy simultaneously increases so the potential energy is converted to kinetic energy.
3.the energy consumed by an object due to its position is known as potential energy
4. potential energy
PE = m g h
m = 10 kg mass of the object
g = 9.8 m/s^2 acceleration of gravity
h= 5 m height of the object from ground
substituting every value in the formula
PE = (10)(9.8)(5)
PE= 490 J
5. potential energy
PE = m g h
but given is the weight and the height of the elevator
W= 1500 N
h= 500 m
but weight of the object is equal to the product of acceleration of gravity and mass of the elevator
so, W = mg
so we can rewrite the formula as PE = Wh
PE = (1500)(500)
PE= 750,000 J
Newton's First Law states that an object would remain at rest or in uniform motion in a straight line unless an unbalanced force acts upon it. So the speed would be the one that remains constant.
Work = Force x Distance = 500 x 4 = 2000 Nm = 2000 J