Answer:
An electric fan is considered to be a mixture of several simple machines. It includes the Wheel and Axle type, wedges, and the Inclined plane types. The blades of an electric fan are the inclined planes and the wedges.
Answer:

Explanation:
Here two charges are placed at distance "d" apart
now the net value of electric field at some position between two charges will be ZERO
so we will have
electric field due to charge 1 = electric field due to charge 2

Let the position where net field is zero will lie at distance "r" from q1

now we will have

now square root both sides

now we have

so we have

Answer:
Q= -6900 J
Explanation:
use the formula Q=mC(T_2 - T_1) and sub in givens
Q=mC(T_2 - T_1)
Q= (200 g)(0.444 J/g°C)(22-100)
Q= -6900 J
The negative sign means heat is lost, which agrees with the decrease in temperature
The magnification of the ornament is 0.25
To calculate the magnification of the ornament, first, we need to find the image distance.
Formula:
- 1/f = u⁻¹+v⁻¹.................... Equation 1
Where:
- f = Focal length of the ornament
- u = image distance
- v = object distance.
make u the subject of the equation
- u = fv/(f+v)................ Equation 2
From the question,
Given:
Substitute these values into equation 2
- u = (12×4)/(12+4)
- u = 48/16
- u = 3 cm.
Finally, to get the magnification of the ornament, we use the formula below.
- M = u/v.................. Equation 3
Where
- M = magnification of the ornament.
Substitute these values above into equation 3
Hence, The magnification of the ornament is 0.25
The answer would be 27,000 Joules because (1/2) m v^2 =30*900 which equals 27,000 J