Answer:
a. The total momentum of the trolleys which are at rest before the separation is zero
b. The total momentum of the trolleys after separation is zero
c. The momentum of the 2 kg trolley after separation is 12 kg·m/s
d. The momentum of the 3 kg trolley is -12 kg·m/s
e. The velocity of the 3 kg trolley = -4 m/s
Explanation:
a. The total momentum of the trolleys which are at rest before the separation is zero
b. By the principle of the conservation of linear momentum, the total momentum of the trolleys after separation = The total momentum of the trolleys before separation = 0
c. The momentum of the 2 kg trolley after separation = Mass × Velocity = 2 kg × 6 m/s = 12 kg·m/s
d. Given that the total momentum of the trolleys after separation is zero, the momentum of the 3 kg trolley is equal and opposite to the momentum of the 2 kg trolley = -12 kg·m/s
e. The momentum of the 3 kg trolley = Mass of the 3 kg Trolley × Velocity of the 3 kg trolley
∴ The momentum of the 3 kg trolley = 3 kg × Velocity of the 3 kg trolley = -12 kg·m/s
The velocity of the 3 kg trolley = -12 kg·m/s/(3 kg) = -4 m/s
We can use the formula Vf^2= Vi^2 + 2ad.
So,
Vi = 0 since we are dropping the object
Therefore,
Vf^2 = 2 (9.8) (49)
You can do the calculator work.
Answer:
Dynamic a, b and d
Deformer c and d
Explanation:
When a force is applied to an object, the acceleration may or may not change, which is analyzed from Newton's second law, this effect is a dynamic effect on the system; The environment can change the shape of the object, in this case the force creates a deformation in it.
With these clarifications let's analyze the different situations.
a) Dynamic. When pushing a car initially an acceleration is created in it, shortly after this decreases to zero and continues with constant speed.
b) Dynamic. When the nail moves it does not change the shape of the body that contains it, nor the shape itself, therefore the system can be analyzed with Newton's second law and the force is of the Dynamic type
c) Deformer. In this case the body (clay) has no net movement, but it does change its shape, so the effect of the force translates into a deformation of the system
d) Deformar and Dynamic. The launch of tennis balls has an initial deformation stage during the acceleration process, in this part the force is of the DEFORMING type, but during the trajectory the deformation disappears and the ball has (gravity) a DYNAMIC action
Answer:
Total energy = 1000J
KE = 500J
PE = 500J
Explanation:
As you may know, the equation for gravitational potential energy is mgh (weight x height)
If the skateboard is halfway down, that means it is at half the height. As the skateboard speeds up (as it goes downward), the potential energy becomes kinetic energy. Since it has 500J of kinetic energy at half way down, it means it had double that amount of Potential energy at the top (1000J). Since half of that became kinetic energy, there is only 500J of PE left.
Total energy = KE + PE = 1000J
KE = 500J
PE = 500J
