Answer:
the googles are 5.3 m from the edge
Explanation:
Given that
depth of pool , d = 3.2 m
Now, let i be the angle of incidence
a laser pointer 0.90 m above the edge of the pool and laser beam enters the water 2.2 m from the edge
⇒tan i = 2.2/0.9
solving we get
i = 67.8°
Using snell's law ,
n1 ×sin(i) = n2 ×sin(r)
n1= refractive index of 1st medium= 1
n2= refractive index of 2nd medium = 1.33
r= angle of reflection
therefore,
r = 44.1°
Now,
distance of googles = 2.2 + d×tan(r)
distance of googles = 2.2 + 3.2×tan(44.1)
distance of googles = 5.3 m
the googles are 5.3 m from the edge
I believe it's b. A flashlight
Potential energy is the an objects energy that is currently not being used but can be used. Example: A ball at the top of a hill is full of potential energy, and as soon as it begins rolling that becomes kinetic energy because it is in use. (Hard to explain but I hope this helps.)
The question isn't clear enough, I think it ask us to calculate the linear speed of a point at the edge of the DVD.
Now let's imagine we're a point at the edge of the DVD, we're undergoing a circular motion. Each minute we will complete a circular track 7200 times, now we need to know the distance we travel each turn. The perimeter of the DVD, a circular object is:
Know recall that:
We now need to know how much distance is traveled during a minute or 60 seconds:
Finally we divide this result with t=60 seconds:
Where the distance units were named units as the length unit is not specified in this exercise.<span />
Answer:
Explanation:
Resistivity is given by where A is cross-sectional area, R is resistance, L is the length and is the reistivity. Substituting 0.0625 for R, 3.14 × 10-6 for A and 3.5 m for L then the resistivity is equivalent to