Answer:
82.4 cm
Explanation:
The object and screen are kept fixed ie the distance between them is fixed and by displacing lens between them images are formed on the screen . In the first case let u be the object distance and v be the image distance
then ,
u + v = 184 cm
In the second case of image formation , v becomes u and u becomes v only then image formation in the second case is possible.
The difference between two object distance ie( v - u ) is the distance by which lens is moved so
v - u = 82.4 cm
Answer:
1.876 J
Explanation:
First, let’s calculate the compression of the spring from the Hooke’s law:
F=kx,
here, F=75 N is the force acted on the spring, k=1500 N⁄m is the force constant of the spring, x is the compression of the spring.
Then, we get:
x=F/k=(75 N)/(1500 N/m)=0.05 m.
Finally, we can find the potential energy stored in the spring:
PE=1/2 kx^2=1/2∙1500 N/m∙(0.05 m)^2=1.875 J.
correct my answer if it's wrong ^^
Answer:
C) Use two batteries instead of one.
Explanation:
-Strength of an electromagnet depends on the electrical current which flows through the wires.
-Two batteries have a higher current than one and thus higher strength in the electromagnet.
It's Photoelectric Effect, I just a test with this same question. I am not good for explaining exactly how, but I was right.
Answer:
The the maximum emf is 
Explanation:
Given that,
Magnetic field 
Frequency = 60 Hz
Diameter = 7.8 μm
We need to calculate the maximum emf
Using formula of emf

Where, N = number of turns
B= magnetic field
A = area
Put the value in to the formula


Hence, The the maximum emf is 