Answer:
Magnitude of the Frictional force = (mv₀²)/2x₁
Explanation:
For the frictional force to stop the box, it has to produce the deceleration of the box; thereby being the opposing force to the box's motion.
According to Newton's first law of motion
Frictional force = (mass of the box) × (deceleration experienced by the box)
Let the mass of the box be m
Then,
Frictional force = ma
Then we can obtain the deceleration using the equations of motion
v² = u² + 2ax
u = Initial velocity = v₀ m/s
v = Final velocity = 0 m/s (since the box comes to rest at the end)
x = horizontal distance covered = (x₁ - x₀) = x₁ (since x₀ = 0)
a = ?
v² = u² + 2ax
0 = (v₀)² + 2ax₁
2ax₁ = - v₀²
a = - (v₀²)/(2x₁) (minus sign, because it's a deceleration)
Magnitude of the Frictional force = ma = (mv₀²)/2x₁
Black holes is exists
Black holes is highly gravitional wave field in space
Use the inverse square law, thus if you move a distance of 3m away, the sound intensity decrease by 1/3^2= 1/9
Answer:
The kinetic energy of the system after the collision is 9 J.
Explanation:
It is given that,
Mass of object 1, m₁ = 3 kg
Speed of object 1, v₁ = 2 m/s
Mass of object 2, m₂ = 6 kg
Speed of object 2, v₂ = -1 m/s (it is moving in left)
Since, the collision is elastic. The kinetic energy of the system before the collision is equal to the kinetic energy of the system after the collision. Let it is E. So,
E = 9 J
So, the kinetic energy of the system after the collision is 9 J. Hence, this is the required solution.
Answer:
A) object moves 20 N [West] or -20 N [East]
B) object moves 6 N [South] or -6 N [North]
C) object moves 90 N [West] or -90 N [East]
D) object does not move and is at rest*
*Rest means 0
Why:
A)both forces from north and south that are pushing against the object neutralize each other. Assume that north is positive and south is negative: 20 [N] + (-20) [S] = 0
On West and east, you can see that west has a greater force. Assume that west is negative and east is positive: 50 [E] + (-70) [W] = -20 [E]
