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Answer:
statement - 'The work done by friction is equal to the sum of the work done by the gravity and the initial push' is correct.
Explanation:
The statement ''The work done by friction is equal to the sum of the work done by the gravity and the initial push" is correct.
The above statement is correct because, the initial push will tend to slide down the block thus the work done by the initial push will be in the downward direction. Also, the gravity always acts in the downward direction. thus, the work done done by the gravity will also be in the downward direction
here, the downward direction signifies the downward motion parallel to the inclined plane.
Now we know that the work done by the friction is against the direction of motion. Thus, the friction force will tend to move the block up parallel to the inclined plane.
Hence, for the block to stop sliding the the above statement should be true.
Answer:
The arrow is at a height of 500 feet at time t = 2.35 seconds.
Explanation:
It is given that,
An arrow is shot vertically upward at a rate of 250 ft/s, v₀ = 250 ft/s
The projectile formula is given by :

We need to find the time(s), in seconds, the arrow is at a height of 500 ft. So,

On solving the above quadratic equation, we get the value of t as, t = 2.35 seconds
So, the arrow is at a height of 500 feet at time t = 2.35 seconds. Hence, this is the required solution.
<span>D) Electromagnetic radiation travels in the form of longitudinal waves.</span>
The resistance expected of the heater is 50.1 ohms.
<h3>What is resistance?</h3>
Resistance can be defined as the opposition to the flow of electric current in an electric circuit. The S.I unit of resistance is Ohms (Ω).
To calculate the resistance of the heater, we use the formula below.
<h3>Formula:</h3>
- R = V²/P............. Equation 1
Where:
- R = Resistance of the heater
- P = Power of the heater
- V = Voltage supplied to the heater
From the question,
Given:
- V = 480 V
- P = 4.6 kW = 4600 W
Substitute these values into equation 1
- R = (480²)/4600
- R = 50.1 ohms.
Hence, the resistance expected of the heater is 50.1 ohms.
Learn more about resistance here: brainly.com/question/17563681