Answer:
a) a = 3.72 m / s², b) a = -18.75 m / s²
Explanation:
a) Let's use kinematics to find the acceleration before the collision
v = v₀ + at
as part of rest the v₀ = 0
a = v / t
Let's reduce the magnitudes to the SI system
v = 115 km / h (1000 m / 1km) (1h / 3600s)
v = 31.94 m / s
v₂ = 60 km / h = 16.66 m / s
l
et's calculate
a = 31.94 / 8.58
a = 3.72 m / s²
b) For the operational average during the collision let's use the relationship between momentum and momentum
I = Δp
F Δt = m v_f - m v₀
F =
F = m [16.66 - 31.94] / 0.815
F = m (-18.75)
Having the force let's use Newton's second law
F = m a
-18.75 m = m a
a = -18.75 m / s²
Answer:
.
Explanation:
The frequency
of a wave is equal to the number of wave cycles that go through a point on its path in unit time (where "unit time" is typically equal to one second.)
The wave in this question travels at a speed of
. In other words, the wave would have traveled
in each second. Consider a point on the path of this wave. If a peak was initially at that point, in one second that peak would be
How many wave cycles can fit into that
? The wavelength of this wave
gives the length of one wave cycle. Therefore:
.
That is: there are
wave cycles in
of this wave.
On the other hand, Because that
of this wave goes through that point in each second, that
wave cycles will go through that point in the same amount of time. Hence, the frequency of this wave would be
Because one wave cycle per second is equivalent to one Hertz, the frequency of this wave can be written as:
.
The calculations above can be expressed with the formula:
,
where
represents the speed of this wave, and
represents the wavelength of this wave.
Answer:
Claim: The heart pumps more blood throughout the body when one exercises because exercise takes a lot of energy from the body.
Evidence: Heart rate went from 80 bpm to 120 bpm
Reasoning: Doing exercise takes a lot of energy to do, causing the circulatory system to have to work harder and pump more blood throughout the body in order to allow someone to be able to do a task that involves so much movement and energy.
Explanation:
Answer:
F = K Q1 Q2 / R^2 where K = 9 * 10E9 (1 / 4 pi ∈0)
F = 9.00E9 * (4.6E-16)^2 / .01 = 1.90E-19 N
Find the number of hours by dividing the distance by mph. The number of hours will be to the left of the decimal point:
250 miles / 65 mph
= 3.846153846
= 3 hours
2) Find the number of minutes by multiplying what is remaining from step 1 by 60 minutes. The minutes will be to the left of the decimal point:
0.846153846 x 60
= 50.76923076
= 50 minutes
3) Find the number of seconds by multiplying what is remaining from step 2 by 60 seconds. The seconds will be to the left of the decimal point:
0.76923076 x 60
= 46.1538456
= 46 seconds
So 3 hours 50 mins and 46 seconds