Answer:
Explanation:
A closed system can exchange energy but not matter, with its surroundings. An isolated system cannot exchange any heat, work, or matter with the surroundings, while an open system can exchange energy and matter.
Hope this helped you!
C..............................
Answer:
The extension of a material or a spring is its increase in length when pulled. Hooke’s Law says that the extension of an elastic object is directly proportional to the force applied to it. In other words:
Explanation:
Answer:
P = 7.28 N.s
Explanation:
given,
initial momentum of cue ball in x- direction,P₁ = 9 N.s
momentum of nine ball in x- direction, P₂ = 2 N.s
momentum in perpendicular direction i.e. y - direction,P'₂ = 2 N.s
momentum of the cue after collision = ?
using conservation of momentum
in x- direction
P₁ + p = x + P₂
p is the initial momentum of the nine balls which is equal to zero.
9 + 0 = x + 2
x = 7 N.s
momentum in x-direction.
equating along y-direction
P'₁ + p = y + P'₂
0 + 0 = y + 2
y = -2 N.s
the momentum of the cue ball after collision is equal to resultant of the momentum .


P = 7.28 N.s
the momentum of the cue ball after collision is equal to P = 7.28 N.s
The velocity of the ferry relative to the current is 4.5 m/s.
<h3>Relative velocity</h3>
- Relative velocity is the velocity of a body as observed from the reference point of another body either stationary or in motion.
Since the river is flowing parallel to the shore and the ferry is moving perpendicular to the shore, their velocities are at right angles to each other.
The two velocities form a right angled-triangle of sides 2, 4 and a hypotenuse which gives the relative velocity of the ferry to the current.
Using Pythagoras rule:
- Let c be the hypotenuse
- a = velocity of the ferry, and
- b = the velocity of the current, and
c² = 4² + 2²
c² = 16 + 4
c = 20
c = √20
c = 4.47 m/s
c ≈ 4.5 m/s
Therefore, the velocity of the ferry relative to the current is 4.5 m/s.
Learn more about relative velocity and Pythagoras rule at: brainly.com/question/25617868