Answer:
Explanation:
Static friction occurs when an object initially starts at rest. When the surfaces of the materials touch, the microscopic unevenness interlock greatest with each other, causing the most friction out of the three.
During sliding friction, an object is already moving or in motion. The microscopic surfaces still interlock, but because the object is in motion, it has a momentum. Therefore, the magnitude of sliding friction is less than that of static friction.
Rolling friction occurs when an object rolls across some surface. Rather than surfaces interlocking, rolling friction is caused by the constant distortion of surfaces. As it rolls, the surfaces of the object are constantly wrapping and changing. This distortion causes the rolling friction. However, it is much less in magnitude when compared to static or sliding friction.
Answer:
Right now I have three.
Explanation: Thanks for the points luv ^-^.
The formula for the density of a substance expressed in mass and volume is rho = mass/volume or p = m/v. Rearranging the formula to isolate volume gives the formula v = m/p. To solve for the problem given, this formula must be used. This gives a solution of:
v = m/p = 250 g/ 968 g/cm^3 = 0.258 cm^3 of sodium
Answer:
80.4 N
Explanation:
As the block is at rest on the slope, it means that all the forces acting on it are balanced.
We are only interested in the forces that act on the block along the direction perpendicular to the slope. Along this direction, we have two forces acting on the block:
- The normal reaction N (contact force), upward
- The component of the weight of the block, , downward, where m is the mass of the block, g is the gravitational acceleration and is the angle of the incline
Since the block is in equilibrium along this direction, the two forces must balance each other, so they must be equal in magnitude:
And by substituting the numbers into the equation, we find the size of the contact force normal to the slope:
It is the energy of the electrons I believe