54:12

WA

brilliants [131]

Answer:

the answers the correct one is d

Explanation:

The speed of sound is constant so we can use the relations of uniform motion

v = x / t

x = v t

now let's calculate the distance for each person

t = 5s

x₁ = 300 5

x₁ = 1500 m

t = 6s

x₂ = 300 6

x₂ = 1800 m

therefore we have two possibilities

a) the two people are on the same side, therefore the distance between them is

Δx = x₂- x₁

Δx = 1800 - 1500

Δx = 300 m

let's reduce to km

Δx = 0.300 km

b) people are on opposite sides of the sound

Δx = x₂ + x₁

Δx = 1800 + 1500

Δx = 3300 m

Δx = 3.3 km

when checking the answers the correct one is d

3 0

3 years ago

14) A race car accelerates from rest to a velocity of 41 m/s in 480 m. What is the acceleration of the race car?

natka813 [3]

Answer:

Explanation:

V₀ = 0 m/s

V = 41 m/s

S = 480 m

___________

a - ?

Distance traveled:

S = (V² - V₀²) / (2*a)

Acceleration :

a = (V² - V₀²) / (2*S)

a = (41² - 0²) / (2*480) = 1.75 m/s²

8 0

1 year ago

A long cylindrical capacitor is made of a central wire of radius a = 2.50 mm surrounded by a conducting shell of radius b = 7.50

asambeis [7]

Answer:

The capacitance per unit length is $5.06\times10^{-11}\ F/m$

(b) is correct option.

Explanation:

Given that,

Radius a= 2.50 mm

Radius b=7.50 mm

Dielectric constant = 3.68

Potential difference = 120 V

We need to calculate charge per length for the capacitance

Using formula of charge per length

$\lambda=\dfrac{4\pi\epsilon_{0}\Delta V}{2 ln(\dfrac{r_{2}}{r_{1}})}$

Put the value into the formula

$\lambda=\dfrac{120}{9\times10^{9}\times2 ln(\dfrac{7.50\times10^{-3}}{2.50\times10^{-3}})}$

$\lambda=6.068\times10^{-9}\ C/m$

We know that,

$\lambda=\dfrac{Q}{L}$

We need to calculate the capacitance per unit length

Using formula of capacitance per unit length

$C=\dfrac{\dfrac{Q}{L}}{\Delta V}$

$C=\dfrac{6.068\times10^{-9}}{120}$

$C=5.06\times10^{-11}\ F/m$

Hence, The capacitance per unit length is $5.06\times10^{-11}\ F/m$

7 0

4 years ago

A series circuit that is connected to a 50 V, 60 Hz source is made up of 25 ohm resistor, capacite wieh X= 18 ohms, and inductor

Allisa [31]

Answer:

the impedance of the circuit is 25.7 ohms.

Explanation:

It is given that,

Voltage, V = 50 volts

Frequency, f = 60 Hz

Resistance, R = 25 ohms

Capacitive resistance, $X_C=18\ ohms$

Inductive resistance, $X_L=24\ ohms$

We need to find the impedance of the circuit. It is given by :

$Z=\sqrt{R^2+(X_L-X_C)^2}$

$Z=\sqrt{25^2+(24-18)^2}$

Z = 25.7 ohms

So, the impedance of the circuit is 25.7 ohms. Hence, this is the required solution.

6 0

3 years ago

Janet was pulling a box that weighed 20N across 5m. How much work did she exert?

Galina-37 [17]

Answer:

100nm

Explanation:

Work=Force×distance

=20×5

=100nm

6 0

2 years ago