Answer:
V = 6.65 [volt]
Explanation:
We must first find the power generated, power is defined as the amount of energy consumed or generated in a given time.
where:
P = power [w]
E = energy = 40 [J]
t = time = 30 [s]
Now we can calculate the voltage or potential drop by means of the power, the power is calculated by means of the product of the voltage by the current.
where:
V = voltage [volts]
I = current = 200mA = 0.2 [A]
Answer:
Explanation:
Using the lens formula
1//f = 1/u+1/v
f is the focal length of the lens
u is the object distance
v is the image distance
For convex lens
The focal length of a convex lens is positive and the image distance can either be negative or positive.
Given f = 20cm and u = 10cm
1/v = 1/f - 1/u
1/v = 1/20-1/10
1/v = (1-2)/20
1/V = -1/20
v = -20/1
v = -20 cm
Since the image distance is negative, this shows that the nature of the image formed by the convex lens is a <u>virtual image</u>
<u></u>
For concave lens
The focal length of a concave lens is negative and the image distance is negative.
Given f = -20cm and u = 10cm
1/v = 1/f - 1/u
1/v = -1/20-1/10
1/v = (-1-2)/20
1/V = -3/20
v = -20/3
v = -6.67 cm
Since the image distance is negative, this shows that the nature of the image formed by the concave lens is a <u>virtual image</u>
<u></u>
Suppose object A<span> is a cue ball and object </span>B<span> is an eight ball on a pool table. If the cue ball strikes the eight ball, the cue ball exerts a force on the eight ball that sends it rolling toward the pocket. At the same time, the eight ball exerts an equal and opposite force on the cue ball that brings it to a stop. Note that both the cue ball and the eight ball each experience a change in momentum. However, the sum of the momentum of the cue ball and the momentum of the eight ball remains constant throughout.</span>
No because the top has more oxygen to it which will break the particles up and have them freeze easier.
so if something froze at the bottom of the lake it would float to the top and that's why water always freezes from the top down :))
<span>To calculate the density, we must first calculate the volume of the object. For a rectangle, the volume is equal to V=l*w*h. In this case, V=22*13.5*12.5=3712.5 mm^3. Next we have to convert the mm^3 to mL using the conversion factor of 1 mm^3=.001 mL. To get mL, we set up the expression 3712.5 mm^3 * (.001mL/1mm^3) = 3.7125 mL. Finally, to get the density, we know density is mass over volume, so we set the expression p=m/V=2.5g/3.7125mL=.6734 which rounded to 3 significant figures is .673. The answer will be .673</span>