Hi! Let's see.
<h3><u>TOPIC: Kinetic Energy.</u></h3>
Explanation:
Data:
- Mass(m) = 2.1 kilograms
- Speed(v) = 30 m/s
- Kinetic Energy(Ek) = ?
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Use the kinetic energy formula:
Replace by the data:
We multiply speed squared:
Multiply in the numerator, without forgetting the units:
Both numerator and denominador operations are divided:
Answer: The kinetic energy is <u>945 Joules.</u>
Cordially Alejanndraax. Greetings!
The image is present at 20cm from the crown glass spherical surface.
To find the answer, we need to know about the lens formula.
<h3>
What's the lens formula?</h3>
- It's (1/V)-(1/U)= (1/f)
- V= image distance from the lens, U= object distance, f= focal length of the lens
<h3>What's the image distance, if object is present at 20cm from crown glass of power 10DS?</h3>
- Focal length (f)= 1/ power = 1/10 = 0.1 m
- U= -20cm = -0.2m (-ve sign due to sign convection)
- (1/V)-(-1/0.2)= (1/0.1)
=> (1/V)+5=10
=> 1/V= 5
=> V=0.2m = 20cm
Thus, we can conclude that the image is present at 20cm.
Learn more about the lens formula here:
brainly.com/question/2098689
#SPJ1
Answer:
Set for what? did U finish the question?
The correct answer is A) <span>The two magnetic fields repel each other, causing the train to levitate, or hover, above the rails.
In fact, same magnetic poles repel each other, while opposite magnetic poles attract each other. the magnets on bottom of the train and on top of the railway have the same polarities, so they repel each other and this allows the train to levitate.
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