Answer:
10 °C
Explanation:
Applying
q = cm(t₂-t₁)............... Equation 2
Where q = heat energy, c = specific heat of ethanol, m = mass of ethanol, t₁ = initial temperature, t₂ = Final temperature.
Given: c = 2.44 J/g.°C, m = 300 g, q = 14640 J, t₂ = 30°C
Substitute into equation 2 and solve for t₁
14640 = 2.44×300(30-t₁)
14640 = 732(30-t₁)
732(30-t₁) = 14640
(30-t₁) = 14640/732
(30-t₁) = 20
t₁ = 30-20
t₁ = 10 °C
Answer: 330 m
Explanation:
The speed of sound
is defined as the distance traveled by the sound wave
in a especific time
:
Where:
is the speed of sound
is half the time the sound wave travels since the person speaks, the sound wave hits the hill and then returns to the person again as an echo
is the distance between the person and the hill
So, we have to find
:


Finally:

Answer:
8 minutes
Explanation:
Part of the question is missing. Complete question is:
<em>Simpson drives his car 144 km with an average velocity of 24 m/s toward the east. How much time would Simpson save by increasing his average velocity to 26m/s East?</em>
Solution:
First of all, we have to calculate the time it takes for Simpson to complete the drive moving at the initial velocity, 24 m/s. We can use the formula:

where
is the displacement
is the velocity
Substituting,

While driving at 26 m/s, the time taken will be

So, Simpson will save 8 minutes.
Answer:
a) v = 88.54 m/s
b) vf = 26.4 m/s
Explanation:
Given that;
m = 1400.0 kg
a)
by using the energy conservation
loss in potential energy is equal to gain in kinetic energy
mg × ( 3200-2800) = 1/2 ×m×v²
so
1400 × 9.8 × 400 = 0.5 × 1400 × v²
5488000 = 700v²
v² = 5488000 / 700
v² = 7840
v = √7840
v = 88.54 m/s
b)
Work done by all forces is equal to change in KE
W_gravity + W_non - conservative = 1/2×m×(vf² - vi²)
we substitute
1400 × 9.8 × ( 3200-2800) - (5 × 10⁶) = 1/2 × 1400 × (vf² -0 )
488000 = 700 vf²
vf² = 488000 / 700
vf² = 697.1428
vf = √697.1428
vf = 26.4 m/s
The answer is going to be element #29 Copper makes blue
Red:#38
Green:#56
Pink:#3
Yellow:#11
Gold:#20
Hopes This Helps