Answer:
v = 12.12 m/s
Explanation:
Given that,
The mass of the cart, m = 75 kg
The roller coaster begins 15 m above the ground.
We need to find the velocity of the cart halfway to the ground. Let the velocity be v. Using the conservation of energy at this position, h = 15/2 = 7.5 m

So, the velocity of the cart is 12.12 m/s.
Answer:
Given that
speed u=4*10^6 m/s
electric field E=4*10^3 N/c
distance b/w the plates d=2 cm
basing on the concept of the electrostatices
now we find the acceleration b/w the plates to find the horizontal distance traveled by the electron when it hits the plate.
acceleration a=qE/m=
=
m/s
now we find the horizontal distance traveled by electrons hit the plates
horizontal distance
![X=u[2y/a]^{1/2}](https://tex.z-dn.net/?f=X%3Du%5B2y%2Fa%5D%5E%7B1%2F2%7D)
=![4*10^6[2*2*10^{-2}/7*10^{14}]^{1/2}](https://tex.z-dn.net/?f=4%2A10%5E6%5B2%2A2%2A10%5E%7B-2%7D%2F7%2A10%5E%7B14%7D%5D%5E%7B1%2F2%7D)
=
= 3 cm
This is the photoelectric effect, and it is best explained by the particle model of light.
<h3>What is the photoelectric effect?</h3>
The photoelectric effect refers to the emission of negatively charged particles and electromagnetic radiation that hits an object.
The photoelectric effect shows how electrons can be released from a given object when this material is absorbing electromagnetic radiation.
The photoelectric effect is a fundamental piece of evidence for understanding the nature of light particles.
Learn more about the photoelectric effect here:
brainly.com/question/1359033
The diameter of the sphere is 2cm.
<h3>How to calculate the diameter?</h3>
From the diagram, the first sphere on the ruler is at 4cn and the last sphere is at 12cm.
Therefore, the length will be:
= 12 - 4.
= 8cm
The diameter of one sphere will be:
= Length / 4
= 8/4
= 2
Therefore, the diameter of the sphere is 2cm.
Note that the second question wasn't found online.
Learn more about diameter on:
brainly.com/question/358744
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