Answer: Fr = 26.53 N
Explanation: The constant force exerted on the block by the surface is the frictional force.
This frictional force is as a result of interaction between the body and the surface.
According to newton's second law of motion,
F - Fr = ma
F=applied force
Fr = magnitude of frictional force
m = mass of object = 12kg
a = acceleration of object = 3.2m/s²
The applied force (F= 75 N) is inclined at an angle of 30° to the horizontal thus making it have 2 components of forces given below
Fx = 75 * cos 30 = 64.95 N (horizontal component)
Fy = 75 * sin 30 = 37.5 N ( vertical motion)
The body moves across the surface, hence the horizontal component of force is responsible for motion.
F = 64.95 N
By substituting the parameters, we have that
64.96 - Fr = 12 * 3.2
64.96 - Fr = 38.4
Fr = 64.96 - 38.4
Fr = 26.53 N
<span>You can start with the equations you know
a=v^2/r = (2pi*r/T)^2/r = 4pi^2r/T^2
Radius of earth (R) = 6378.1 km
Time in one day (T) = 86400 seconds
Latitude = 44.4 degrees
If you draw a circle and have the radius going out at a 44.4 degree angle above the center you can then find the r.
r=Rcos(44.4)
r=6378.1cos(44.4)
r= 4556.978198 km or 4556978 m
Now you can plug this value into the acceleration equation from above...
a= 1.8*10^8/7.47*10^9
a= .0241 m/s^2 </span>
Answer:
641 nm.
Explanation:
Given that,
A transmission grating has 5200 slits/cm.
We need to find the longest wavelength that can be observed in the third order. Using grating equation as follows :
...(1)
d is slit spacing
No fo slit per unit length :

We know that, N = 1/d
For longest wavelength, θ = 90°
From equation (1)

Hence, the longest wavelength in third order for a transmission grating is 641 nm.
Answer:
The fundamental law of magnetism states that like poles repel and unlike poles attracts each other
North and South = attraction
South and North = attraction
Explanation:
What are magnetic poles?
The magnetic poles are the two points at The end of a magnetic bar in which the magnetic properties are most pronounced.
When two opposite magnetic poles are close, they attract each other. When like poles are pushed together, there is a force of repulsion. The rule for magnets is that like poles repel and unlike poles attract.
Answer:increases
Explanation:
If we are going upward in an elevator from the ground floor to the top floor then it indicates that your distance from the center of the earth is increasing while the time period remains the same.
If the radial distance is increased then the tangential velocity of the object must be increased because the time period is the same.
This can be best explained by taking an example of a car moving in a circle of radius r. If radial is increased for the same period then the car has to travel at a higher velocity to make in time.