Answer:
a. by moving the book without acceleration and keeping the height of the book constant
Explanation:
FOR CONSTANT KINETIC ENERGY:
The kinetic energy of a body depends upon its speed according to its formula:
ΔK.E = (1/2)mΔv²
So, for Δv = 0 m/s
ΔK.E = 0 J
So, for keeping kinetic energy constant, the books must be moved at constant speed without acceleration.
FOR CONSTANT POTENTIAL ENERGY:
The potential energy of a body depends upon its height according to its formula:
ΔP.E = mgΔh
So, for Δh = 0 m/s
ΔP.E = 0 J
So, for keeping potential energy constant, the books must be moved at constant height.
So, the correct option is:
<u>a. by moving the book without acceleration and keeping the height of the book constant</u>
Please elaborate more on your question so I can help you
Answer: True
Explanation: When light is reflected off lets say a mirror it is bent and changes direction to bounce off of another wall or object. For example if you take a flash light and shine it into a mirror the light reflects into a different direction your welcome
Answer: 55 ohms
Explanation:
Given that,
Voltage of heater (v) = 110-volt
Current drawn by heater (I) = 2.0 amperes
resistance of the heater (r) = ?
Since voltage, current and resistance are involved, apply the formula for ohms law.
Voltage = current x resistance
i.e v = ir
where r = v / i
r = 110 volts / 2.0 A
r = 55 ohms
Thus, the resistance of the heater is 55 ohms
Answer:
50% of it .
Explanation:
50% of it is illuminated by the Sun.