The magnitude of the net force could be anything from 89N to 341N , and it could be acting in ANY direction.
To solve both mysteries we need to know the directions of the original two forces.
Answer:
v = 14.41 m/s
Explanation:
It is given that,
mass of the ball, m = 200 g = 0.2 kg
Height of the roof, h = 12 m
The ball is tossed 1.4 m above the ground, h' = 1.4 m
Let v is the minimum speed with which the ball is tossed. Using the conservation of energy to find it as :





v = 14.41 m/s
So, the minimum speed with which the ball is thrown straight up is 14.41 m/s. Hence, this is the required solution.
Answer:
v = 8.1 m/s
θ = -36.4º (36.4º South of East).
Explanation:
- Assuming no external forces acting during the collision (due to the infinitesimal collision time) total momentum must be conserved.
- Since momentum is a vector, if we project it along two axes perpendicular each other, like the N-S axis (y-axis, positive aiming to the north) and W-E axis (x-axis, positive aiming to the east), momentum must be conserved for these components also.
- Since the collision is inelastic, we can write these two equations for the momentum conservation, for the x- and the y-axes:
- We can go with the x-axis first:

⇒ 
- Replacing by the givens, we can find vfx as follows:

- We can repeat the process for the y-axis:

⇒
- Replacing by the givens, we can find vfy as follows:

- The magnitude of the velocity vector of the wreckage immediately after the impact, can be found applying the Pythagorean Theorem to vfx and vfy, as follows:

- In order to get the compass heading, we can apply the definition of tangent, as follows:

⇒ tg θ = vfy/vfx = (-4.8m/s) / (6.5m/s) = -0.738 (9)
⇒ θ = tg⁻¹ (-0.738) = -36.4º
- Since it's negative, it's counted clockwise from the positive x-axis, so this means that it's 36.4º South of East.
Answer:
Explanation:
T = 2π √l/g
The dimension for l = m
The dimension for g = m/s²
The dimension for 2π is nothing. Since it's a constant, it is dimensionless.
Now we proceed ahead. Since we are not using the 2π, for the sake of this proving, our formula will temporarily be written as
T = √l/g
Inputting the dimensions, we have
T = √(m) / (m/s²)
T = √(m * s²/m)
T = √s²
T = s
Since the unit of period itself is in s, we can adjudge that the equation is dimensionally constant.