Answer:
The sled needed a distance of 92.22 m and a time of 1.40 s to stop.
Explanation:
The relationship between velocities and time is described by this equation:
, where
is the final velocity,
is the initial velocity,
the acceleration, and
is the time during such acceleration is applied.
Solving the equation for the time, and applying to the case:
, where
because the sled is totally stopped,
is the velocity of the sled before braking and,
is negative because the deceleration applied by the brakes.
In the other hand, the equation that describes the distance in term of velocities and acceleration:
, where
is the distance traveled,
is the initial velocity,
the time of the process and,
is the acceleration of the process.
Then for this case the relationship becomes:
.
<u>Note that the acceleration is negative because is a braking process.</u>
This can be answered using the beat frequency formula, which is simply the difference between 2 frequencies.
Let: <span>fᵇ = beat frequency
</span>f₁ = first frequency
f₂ = second frequency
fᵇ = |f₁ - f₂|
substituting the values:
fᵇ = |24Hz - 20Hz|
fᵇ = 4Hz
The unit Hz also means beats per second, therefore:
<span>fᵇ = 4 beats per second
</span>
Therefore, the answer is C. 4
Answer:
Fnet - Fg
Explanation:
When an object is in an elevator, its weight varies with respect to the direction of movement of the elevator and the elevators acceleration.
The weight, W, of an object can be expressed as;
W = mg
where m is the object's mass, and g is the acceleration due gravity.
If the object is in an elevator that speed up, an apparent weight would be felt since both mass and elevator are moving against gravitational pull of the earth.
So that,
= mg + ma
where: mg is the weight of the object, and ma is the apparent weight.
Apparent weight (ma) =
- mg
Answer:
20 m/s westward
Explanation:
Taking eastward as positive direction, we have:
is the velocity of Bill with respect to Amy (which is stationary)
is the velocity of Carlos with respect to Amy
Bill is moving 5 m/s eastward compared to Amy at rest, so the velocity of Bill's reference frame is

Therefore, Carlos velocity in Bill's reference frame will be

and the direction will be westward (negative sign).
Answer:
3k mph
Explanation:
don't take my answer it is wrong