You can do this two ways:
1). Whatever kinetic energy the rolling ball has is the amount
of energy you have to absorb in order to stop it.
2). Whatever momentum the rolling ball has is the amount of
momentum you have to provide in the other direction to cancel it.
Since you asked about force and time, we sense 'impulse' in the
air, and we know that impulse is exactly a change in momentum.
So let's use #2 and talk about momentum and impulse.
Impulse = (force) x (time)
Momentum of a moving object is (mass) x (speed) .
-- Momentum of the first ball: (8 kg) x (0.2 m/s) = 1.6 kg-m/s
Impulse required to stop it = 1.6 kg-m/s
(force) x (10 sec) = 1.6
Force required = 1.6 / 10 = 0.16 Newton .
-- Momentum of the second ball: (4 kg) x (1 m/s) = 4 kg-m/s
Impulse required to stop it = 4 kg-m/s
(force) x (10 sec) = 4
Force required = 4 / 10 = 0.4 Newton .
You need more force o stop the second ball. Although its mass
is only 1/2 the mass of the 8kg ball, it's moving 5 times as fast,
and has 2.5 times the momentum of the bigger ball.
So you need 2.5 times as much impulse to stop it.
If you're going to push on each ball for the same length of time,
then you need to push 2.5 times as hard on the smaller ball in
order to stop it.
Single
Displacement Reaction Definition. A
single displacement reaction is a chemical reaction where one reactant is exchanged for one ion of a second reactant. It is also known as a
single replacement reaction.
Answer:
a 1-mm wide capillary inserted vertically into the water
Explanation:
When you introduce the capillary tube upright in the liquid and observe how the height of liquid in the capillary increases as time goes by.
When the liquid of viscosity h, ascends through the capillary tube of radius r, we will assume that it flows in a laminar regime, we apply the Poiseuille law.
When the pressure difference becomes zero, Dp = 0, the equilibrium situation studied in the previous section is reached. The liquid stops ascending through the capillary tube. The height at which the liquid rises is maximum when the capillary is 1 mm thick and is introduced vertically into the water
Given Information:
Number of turns = N = 1130 turns
Length of solenoid = L = 0.430 m
Magnetic field = B = 1.0x10⁻⁴ T
Required Information:
Current = I = ?
Answer:
I = 0.0302 A
Explanation:
The current flowing in the solenoid winding can be found using
I = BL/μ₀N
Where μ₀ is the permeability of free space, N is the number of turns, B is the magnetic field and L is the length of solenoid
I = 1.0x10⁻⁴*0.430/4πx10⁻⁷
*1130
I = 0.0302 A
or
I = 30.28 mA
Answer:
The friction of the string and its pivotal anchor point cannot be eliminated. The precise measurement of the length of the pendulum is difficult to take by using meter sticks or rulers. The value of the acceleration due to gravity g in the locality is not constant and must be obtained from reliable sources.
