loudness is directly proportional to amplitude.

so, if amplitude is increased there will be an increase in loudness.

**Answer:**

Barret True, the speed decreases with increasing time

**Explanation:**

The equation they give us to describe the movement is of the form

y = yo + v₀ t + ½ a t²

The given equation is

y = -4 - 9 t + 2 t²

We can match term to term and find the constants

y₀ = -4 m

v₀ = -9 m / s

a = 2 m / s²

With this data we can build the equation of speed and time

v = v₀ + a t

v = - 9 + 2 t

With this expression we see that as time increases the speed decreases since the speed and acceleration have direction is opposite

Now we can analyze the students' observations

Amadeo False, we see that the behavior is the opposite

Barret True, the speed decreases with increasing time

Chinue False With the equation we have all the data to build the speed equation as a function of time

You would know the period of the planets orbit.

**Answer:**

**Explanation:**

The **equation that relates** heat Q with the temperature change of a substance of mass <em>m </em>and specific heat <em>c </em>is .

We want to calculate the final temperature <em>T, </em>so we have:

Which for our values means (in this case we do not need to convert the mass to Kg since <em>c</em> is given in g also and they cancel out, but we add to our temperature in to have it in as it must be):

**Explanation:**

Given:

Δx = 50 m

v₀ = 0 m/s

a = 0.2 m/s²

Find: v

The problem does not involve time. Therefore, the required equation is:

v² = v₀² + 2aΔx

Plug in values and solve:

v² = (0 m/s)² + 2 (0.2 m/s²) (50 m)

v = 4.47 m/s