One is when you are measuring a distance in space! I don't know the other but hope you find another example!
Explanation :
It is given that, a heavy box is in the back of a truck and the truck is accelerating to the right.
The description is shown in<em> figure 1</em>. Here, the forces that act on both box and the truck are the normal force, the frictional force and their weight mg.
The free body diagram is shown in <em>figure 2</em>. This shows the total forces ( F = ma )acting on the truck. As a result, the truck will move in a forward direction.
Hence, this is the required explanation.
Answer: the basic unit of a chemical element.
Explanation:
An atom is the smallest unit of ordinary matter that forms a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across.
hope this helps
Answer: F = mg(1 + 4m / (½M + m))
Explanation:
"At this point seems" unclear. If the particle is at the top of the disc and angular velocity is negligible, then the force would equal the weight of the particle. F = mg
The more interesting question would be what force is needed to keep the particle attached when significant angular rotation has been achieved. The maximum point would be diametrically opposed to the starting point.
I will analyze it there
The potential energy will convert to kinetic energy
mgh = ½Iω²
mg(2R) = ½(½MR² + mR²)ω²
4mgR = R²(½M + m)ω²
ω² = 4mg / (R(½M + m))
With m at the lowest position, the force of attachment must support the weight of m and provide for the needed centripetal acceleration
F = m(g + ω²R)
F = m(g + 4mg / (R(½M + m))R)
F = mg(1 + 4m / (½M + m))
Answer:
2.55348650884 m/s
2.67400481907 m/s²
10.6960192763 m/s²
Explanation:
d = Diameter of the ride = 16 ft=
r = Radius = 
t = Time taken = 6 seconds
Velocity is given by

The speed is 2.55348650884 m/s
Acceleration is given by

The acceleration is 2.67400481907 m/s²
When the speed is halved


The acceleration is 10.6960192763 m/s²