Answer:
Answer: It takes 5,730 years for half the carbon-14 to change to nitrogen; this is the half-life of carbon-14. After another 5,730 years only one-quarter of the original carbon-14 will remain
The frictional force is directly proportional to the force that is perpendicular on the surface.
When the body is placed on a horizontal level with zero inclination, the only force acting on the body is the gravitational force which always pulls the body down. The gravitational force, in this case, is the perpendicular force to the surface. Accordingly, this entire force is used to generate friction
Now as the inclination of the surface increases, the gravitational force is no longer the perpendicular force of the body, its value decreases, which means only a part is used to generate frictional force. Consequently, frictional force decreases.
When the inclination reaches 90 degrees, the gravitational force does not act along the normal and accordingly, no friction force is generated.
Answer:
U² = 142.86 N
U¹ = 357.14 N
Explanation:
Taking summation of the moment about point A, we get the following equilibrium equation: (taking clockwise direction as positive)

where,
W = weight of boy = 500 N
U² = reaction ay B = ?
Therefore,

<u>U² = 142.86 N</u>
Now, taking summation of forces on the plank. Taking upward direction as positive, for equilibrium position:

<u>U¹ = 357.14 N</u>
Gauss law states that the electric flux through any closed
surface is proportional to the net electric charge inside the surface. This is
expressed mathematically in the form of:
Φ = Q / εo
Where,
Φ = the electric flux = unknown (which we have to find for)
Q = the net electric charge = 5.0 µC = 5 E-6 C
εo = the permittivity of free space = a constant value =
8.85 E-12 C^2 / N m^2
Plugging in the values
into the equation will result in:
Φ = 5 E-6
C / (8.85 E-12 C^2 / N m^2)
Φ = 564,971.75 Wb = <span>5.6 x
10^5 Wb </span>
Answer:height above ground at which projectile have velocity
0.5v is (0.0375v^2)
Explanation:
Using Vf = Vi - gt
Where Vf is final velocity
Vi is initial velocity
g is the acceleration due to gravity
t is the time taken
So, 0.5v = v - gt
t = 0.05v
Therefore height h = vt - 0.5gt^2
Subtitute t
h = 0.05v^2 - 0.0125v^2
h = 0.0375v^2