Answer:
18.82 m
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 20 m/s
Horizontal distance (s) = 39.2 m
Height (h) of the cliff =?
Next, we shall determine the time taken for the car to get to the ground. This can be obtained as follow:
Initial velocity (u) = 20 m/s
Horizontal distance (s) = 39.2 m
Time (t) taken to reach the ground =?
s = ut
39.2 = 20 × t
Divide both side by 20
t = 39.2 / 20
t = 1.96 s
Finally, we shall determine the height of the cliff as follow:
Acceleration due to gravity (g) = 9.8 m/s²
Time (t) taken to reach the ground = 1.96 s
Height (h) of the cliff =?
h = ½gt²
h = ½ × 9.8 × 1.96²
h = 4.9 × 3.8416
h = 18.82 m
Therefore, the cliff is 18.82 m high
I believe the answer is C. an increase in the number of cold climates
Answer:
pf = 198.8 kg*m/s
θ = 46.8º N of E.
Explanation:
- Since total momentum is conserved, and momentum is a vector, the components of the momentum along two axes perpendicular each other must be conserved too.
- If we call the positive x- axis to the W-E direction, and the positive y-axis to the S-N direction, we can write the following equation for the initial momentum along the x-axis:

- We can do exactly the same for the initial momentum along the y-axis:

- The final momentum along the x-axis, since the collision is inelastic and both objects stick together after the collision, can be written as follows:

- We can repeat the process for the y-axis, as follows:

- Since (1) is equal to (3), replacing for the givens, and since p₀Bₓ = 0, we can solve for vfₓ as follows:

- In the same way, we can find the component of the final momentum along the y-axis, as follows:

- With the values of vfx and vfy, we can find the magnitude of the final speed of the two-object system, applying the Pythagorean Theorem, as follows:

- The magnitude of the final total momentum is just the product of the combined mass of both objects times the magnitude of the final speed:

- Finally, the angle that the final momentum vector makes with the positive x-axis, is the same that the final velocity vector makes with it.
- We can find this angle applying the definition of tangent of an angle, as follows:

⇒ θ = tg⁻¹ (1.06) = 46.8º N of E
Answer:
Fg = 98.1 [N]; N = 98.1 [N]; Ff = 39.24 [N]; a = 2.076[m/^2]
Explanation:
To solve this problem, we must make a free body diagram and interpret each of the forces acting on the box. In the attached diagram we can find the free body diagram.
The gravitational force is equal to:
Fg = (10 * 9.81) = 98.1 [N]
Now by summing forces on the Y axis equal to zero, we can find the normal force exerted by the surface.
N - Fg = 0
N = Fg
N = 98.1 [N]
The friction force is defined as the product of normal force by the coefficient of friction.
Ff = N * μ
Ff = 98.1 * 0.4
Ff = 39.24 [N]
By the sum forces on the x-axis equal to the product of mass by acceleration (newton's second law), we can find the value of acceleration.
60 - Ff = m * a
60 - 39.24 = 10 * a
a = 2.076[m/^2]