Answer:
v_{ average} = 5.57
Explanation:
The most probable value of a measure is
v_average = ∑ x_i
where N is the number of measurements
in tes case N = 3
v_{average} = ⅓ (5.63 +5.54 + 5.53)
V_{average} = 5,567
The number of significant figures must be equal to the number of figures that have the least in the readings.
v_{ average} = 5.57
Answer:
The two types of energy possessed by the roller coaster are:
- Potential energy: it is the energy possessed by the roller coaster due to its position. It is calculated as
where
m is the mass of the roller coaster
g is the acceleration due to gravity
h is the height of the roller coaster relative to the ground
- KInetic energy: it is the energy possessed by the roller coaster due to its motion. It is calculated as
where
v is the speed of the roller coaster
Moreover, according to the law of conservation of energy, the total mechanical energy of the roller coaster (the sum of potential+kinetic energy) is constant during the motion:
This implies that:
- When PE increases (because h increases), KE decreases (because v decreases)
- When PE decreases (because h decreases), KE increases (because v increases)
Now we can apply these conclusions to the motion of the roller coaster:
- When it moves from A to B, potential energy is converted into kinetic energy, so PE decreases and KE increases
- When it moves from B to C, kinetic energy is converted into potential energy, so PE increases and KE decreases
- When it moves from C to D, potential energy is converted into kinetic energy, so PE decreases and KE increases
- When it moves from D to E, kinetic energy is converted into potential energy, so PE increases and KE decreases
Answer:
a) I = 3.63 W / m² , b) I = 0.750 W / m²
Explanation:
The intensity of a sound wave is given by the relation
I = P / A = ½ ρ v (2π f )²
I = (½ ρ v 4π² s_{max}²) f²
a) with the initial condition let's call the intensity Io
cte = (½ ρ v 4π² s_{max}²)
I₀ = cte s² f₀²
I₀ = cte 10 6
If frequency is increase f = 2.20 10³ Hz
I = constant (2.20 10³) 2
I = cte 4.84 10⁶
let's find the relationship of the two quantities
I / Io = 4.84
I = 4.84 Io
I = 4.84 0.750
I = 3.63 W / m²
b) in this case the frequency is reduced to f = 0.250 10³ Hz and the displacement s = 4 s or
I = cte (f s)²
I = constant (0.250 10³ 4)²
I = cte 1 10⁶
the relationship
I / Io = 1
I = Io
I = 0.750 W / m²