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
Answer:
1) 
2)
Explanation:
Given data:
speed of sound v = 1540 m/s
frequency f = 1.40 MHz = 1.40 \times 10^6 Hz
density 
1) we know that
2) we know that
This is a question about converting energy from one form to another.
<span>While it is sitting on the ledge, it isn't moving, so at that point it doesn't have any kinetic energy. What it has is gravitational potential energy due to its height above the ground. </span>
<span>Just as it lands, it's at ground level, so it doesn't have any gravitational potential energy anymore. </span>
<span>The reason is that on the way down, it sped up, so all its original gravitational potential energy was turned into kinetic energy. </span>
<span>So if you can work out how much potential energy it had to start with, you will know that that is how much kinetic energy it ended up with just before it landed. </span>
<span>potential energy = m * g * h </span>
<span>where m is the mass, g is the acceleration due to gravity and h is the height </span>
potential energy = 4.45 * 9.81 * 0.800 = 35.3 J
Hope that helps. Please give me Brainlyest answer. :]
Answer:
1428.6m/s²
Explanation:
Given parameters:
Force applied on the body = 40N
Mass of the body = 28g
1000g = 1kg
28g will therefore be 0.028kg
Unknown:
Acceleration = ?
Solution:
To solve this problem, we use the expression derived from Newton's second law of motion.
Force = mass x acceleration
Insert the parameters and solve;
40 = 0.028 x acceleration
Acceleration = 
= 1428.6m/s²
Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space.
