<span> The boiling point of water at sea level is 100 °C. At higher altitudes, the boiling point of water will be.....
a) higher, because the altitude is greater.
b) lower, because temperatures are lower.
c) the same, because water always boils at 100 °C.
d) higher, because there are fewer water molecules in the air.
==> e) lower, because the atmospheric pressure is lower.
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Water boils at a lower temperature on top of a mountain because there is less air pressure on the molecules.
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I hope this is helpful. </span>
Answer:
Kinetic Energy
Explanation:
The potential energy is being converted into kinetic energy. The hitter has struck the ball transferring the kinetic energy from the swinging bat to the ball.
Answer:
11.7 m
Explanation:
I assume north is the y direction and x is the east direction, so Δx refers to the displacement in the east direction.
First, find the time it takes for the velocity to change from directly north to directly east.
Given (in the y direction):
v₀ = 2.88 m/s
v = 0 m/s
a = 0.350 m/s² sin(-52.0°) = -0.276 m/s²
Find: t
v = at + v₀
(0 m/s) = (-0.276 m/s²) t + (2.88 m/s)
t = 10.4 s
Given (in the x direction):
v₀ = 0 m/s
a = 0.350 m/s² cos(-52.0°) = 0.215 m/s²
t = 10.4 s
Find: Δx
Δx = v₀ t + ½ at²
Δx = (0 m/s) (10.4 s) + ½ (0.215 m/s²) (10.4 s)²
Δx = 11.7 m
Answer:
θ = 12.60°
Explanation:
In order to calculate the angle below the horizontal for the velocity of the hockey puck, you need to calculate both x and y component of the velocity of the puck, and also you need to use the following formula:
(1)
θ: angle below he horizontal
vy: y component of the velocity just after the puck hits the ground
vx: x component of the velocity
The x component of the velocity is constant in the complete trajectory and is calculated by using the following formula:

vo: initial velocity = 28.0 m/s
The y component is calculated with the following equation:
(2)
voy: vertical component of the initial velocity = 0m/s
g: gravitational acceleration = 9.8 m/s^2
y: height
You solve the equation (2) for vy and replace the values of the parameters:

Finally, you use the equation (1) to find the angle:

The angle below the horizontal is 12.60°
The car is initially traveling north at 17.7 m/s, and after 12 s, its velocity is 14.1 m/s, still due north. This means that the direction of the car has not changed, so we can already say that the direction of the acceleration is north (if the magnitude of the acceleration is positive) or south (if the magnitude of the acceleration is negative).
To find the magnitude of the average acceleration, we must calculate the ratio between the change in velocity and the time taken:

Since the acceleration is negative, it means it is in the opposite direction to the motion of the car, therefore south. Therefore, the correct answer is
b) 0.30 m/s2, south