Answer:
D. 2.8 × 10⁹ N
Explanation:
The force between two charges is directly proportional to the amount of charges at the two points and inversely proportional to the square of distance between the two points.
Fe= k Q₁Q₂/r²
Q₁= -0.0045 C
Q₂= -0.0025 C
r= 0.0060 m
k= 9.00 × 10 ⁹ Nm²/C²
Fe= (9.00 × 10 ⁹ Nm²/C²×-0.0045 C×-0.0025 C)/0.0060²
=2.8 × 10⁹ N
Answer:
The first part can be solved via conservation of energy.
For the second part,
the free body diagram of the car should be as follows:
- weight in the downwards direction
- normal force of the track to the car in the downwards direction
The total force should be equal to the centripetal force by Newton's Second Law.
where because we are looking for the case where the car loses contact.
Now we know the minimum velocity that the car should have. Using the energy conservation found in the first part, we can calculate the minimum height.
Explanation:
The point that might confuse you in this question is the direction of the normal force at the top of the loop.
We usually use the normal force opposite to the weight. However, normal force is the force that the road exerts on us. Imagine that the car goes through the loop very very fast. Its tires will feel a great amount of normal force, if its velocity is quite high. By the same logic, if its velocity is too low, it might not feel a normal force at all, which means losing contact with the track.
Answer:
D) 763 nm
Explanation:
Calculation for the wavelength of light
Using this formula
Wavelength of light=Delta Y*Distance / Length
Where,
Delta Y represent the 2nd order bright fringe
Length represent the distance between both the slits and the screen
Distance represent the Distance between the slits
Let note that cm to m = (4.2) x 10^-2 and mm to m= ( 0.0400x 10^-3)
Now Let plug in the formula
Wavelength of light=[(4.2 x 10^-2m)(0.0400 x 10^-3m) / 2(1.1m)]*10^-7 meters
Wavelength of light=[(0.042m) (0.0004m)/2.2m]*10^-7 meters
Wavelength of light =(0.0000168m/2.2m)*10^-7 meters
Wavelength of light =7.63 *10^-7 meters
Wavelength of light =763 nm
Therefore the Wavelength of light will be 763 nm