Help me with this review question please.

Answer:

The rocket will appear larger than it actually is

Answer:

Change in KE = +1.96×10^4 J while the change in ME = 0 J

Answer:

28.7%

Explanation:

efficiency = work output /work input × 100

Answer:

11.5 m/s²

Explanation:

The centripetal acceleration, a = rω² where r = radius of cylinder = 10.7 cm = 0.107 m and ω = angular speed = 2πN where N = number of revolutions per second = 1.65 rev/s

So, a = rω²

a = r(2πN)²

a = 4π²rN²

substituting the values of the variables into the equation, we have

a = 4π²rN²

a = 4π²(0.107 m)(1.65 rev/s)²

a = 4π²(0.107 m)(2.7225 rev²/s)²

a = 4π² × 0.2913075 mrev²/s)²

a = 11.5 m/s²

2:5

Explanation:

400g : 1kg

400g: 1000g

4 : 10

2 : 5

Answer:

question #1 is A

Question #2 is C

Explanation:

Answer:

i guess the answer is false

I believe the answer is a

Answer:

Please I do not understand the instructions given at the end of the question

Answer:

the length of the wire is 134.62 m.

Explanation:

Given;

resistivity of the copper wire, ρ = 2.6 x 10⁻⁸ Ωm

cross-sectional area of the wire, A  = 35 x 10⁻⁴ cm² = ( 35 x 10⁻⁴) x 10⁻⁴ m²

resistance of the wire, R = 10Ω

The length of the wire is calculated as follows;

[tex]R = \frac{\rho L}{A} \\\\L = \frac{RA}{\rho} \\\\L= \frac{10 \times (35\times 10^{-4}) \times 10^{-4}}{2.6 \times 10^{-8}} \\\\L = 134.62 \ m[/tex]

Therefore, the length of the wire is 134.62 m.

Answer:

too many

Explanation:

Answer:

W = 1/2 K x^2

x^2 = 2 * W / K = 2 * 49 J / (N/m)  = .218 / m^2

x =  .467 m

Answer:

- the expected value is 8

- the standard deviation is 2.8284

Explanation:

Given the data in the question;

The model N(t), the number of planets found up to time t, as a poisson process,

∴ N(t) has distribution of poisson distribution with parameter (λt)

so

the mean is;

λ = 1 every month = 1/3 per month

E[N(t)] = λt

E[N(t)] = (1/3)(24)

E[N(t)] = 8

Therefore, the expected value is 8

For poisson process, Variance and mean are the same,

Var[N(t)] = Var[N(24)]

Var[N(t)] = E[N(24)]

Var[N(t)] = 8

so the standard deviation will be;

σ[N(24)] = √(Var[N(t)] )

σ[N(24)] = √(8 )

σ[N(24)] = 2.8284

Therefore, the standard deviation is 2.8284

Answer:

475.7 m/s

Explanation:

Given,

Frequency ( f ) = 67 Hz

Wavelength ( λ ) = 7.1 m

To find : Speed ( v ) = ?

Formula : -

v = f λ

v

= 67 x 7.1

= 475.7 m/s

Therefore,

the speed of the wave is 475.7 m/s.

Answer:

the frequency of the second harmonic of the pipe is 425 Hz

Explanation:

Given;

length of the open pipe, L = 0.8 m

velocity of sound, v = 340 m/s

The wavelength of the second harmonic is calculated as follows;

L = A ---> N   +  N--->N   +   N--->A

where;

L is the length of the pipe in the second harmonic

A represents antinode of the wave

N represents the node of the wave

[tex]L = \frac{\lambda}{4} + \frac{\lambda}{2} + \frac{\lambda}{4} \\\\L = \lambda[/tex]

The frequency is calculated as follows;

[tex]F_1 = \frac{V}{\lambda} = \frac{340}{0.8} = 425 \ Hz[/tex]

Therefore, the frequency of the second harmonic of the pipe is 425 Hz.

The frequency of the second harmonic of the pipe is 425 Hz.

Frequency is the number of oscillations per second in the sinusoidal wave.

Given is length of the open pipe, L = 0.8 m, and velocity of sound, v = 340 m/s

The wavelength of the second harmonic is represented as

L = A → N   +  N→N   +   N→A

where, L is the length of the pipe in the second harmonic, A represents antinode of the wave, N represents the node of the wave

Length = λ/4 +λ/2 +λ/4

Length = λ

The frequency is calculated

frequency = speed of light / wavelength

Put the values, we get

f = 340/0.80

f = 425 Hz

Therefore, the frequency of the second harmonic of the pipe is 425 Hz.

Learn more about frequency.

https://brainly.com/question/25867078

#SPJ5

Answer:

The force will be "9.8 N".

Explanation:

The given values are:

mass,

m = 0.7 kg

M = 2

g = 9.8

Now,

⇒  [tex]\tau = T \alpha[/tex]

then,

⇒  [tex]\frac{1}{2}mR^2(\frac{1}{R}\frac{dv}{dt}) =M(g-a_t)R[/tex]

⇒  [tex]\frac{1}{2}m \ a_t=m(g-a_t)[/tex]

⇒  [tex]a_t=\frac{2g}{(\frac{m}{M} +2)}[/tex]

On substituting the values, we get

⇒      [tex]=\frac{2\times 9.8}{\frac{0.7}{2} +2}[/tex]

⇒      [tex]=8.34 \ m/s[/tex]

hence,

⇒  [tex]T=mg+M(g-a_t)[/tex]

On substituting the values, we get

⇒      [tex]=0.7\times 9.8+2(9.8-8.34)[/tex]

⇒      [tex]=6.86+2(1.46)[/tex]

⇒      [tex]=6.86+2.92[/tex]

⇒      [tex]=9.8 \ N[/tex]

Answer:

6.26 m/s

Explanation:

Since we are neglecting viscous losses and surface tension effects in the liquid jet, by conservation of energy, the potential energy loss of the jet = kinetic energy gain of the jet

So, mgh = 1/2mv² where m = mass of water in jet, g = acceleration due to gravity = 9.8 m/s², h = height of outlet = 2.0 mand v = velocity of liquid jet

So, mgh = 1/2mv²

gh = 1/2v²

v² = 2gh

v = √(2gh)

v = √(2 × 9.8 m/s² × 2.0 m)

v = √(39.2 m²/s²)

v = 6.26 m/s

Answer:

Distance travel by go-cart = 500 meter

Explanation:

Given:

Speed of go cart = 25 m/s

Time travel = 20 seconds

Find:

Distance travel by go-cart

Computation:

Distance = Speed x time

Distance travel by go-cart = Speed of go cart x Time travel

Distance travel by go-cart = 25 x 20

Distance travel by go-cart = 500 meter

Answer:

5.48 m/s.

Explanation:

Use the formula a=v^2/r.

Answer:

If light enters any substance with a higher refractive index (such as from air into glass) it slows down. The light bends towards the normal line. If light travels enters into a substance with a lower refractive index (such as from water into air) it speeds up. The light bends away from the normal line.

Answer:

5,000-10,000 K

Explanation:

make me your brainlist pls

Answer:

The average speed throughout the journey was 76.36 kilometers per hour.

Explanation:

Given that a car driver spends 3hrs driving at an average speed of 80km / hr, stops for 30 minutes to have some rest, and then drives at an average speed of 90km / hr for 2 hours, to determine the average speed during the whole journey the following calculation must be performed:

80 km / h x 3 = 240 km

90 km / h x 2 = 180 km

240 + 180 = 420 km

3 + 2 + 0.5 = 5.5 hours

420 / 5.5 = 76.36

Thus, the average speed throughout the journey was 76.36 kilometers per hour.

Answer:

xplanation:

Angle of reflection is measured between the incident ray and the angle which it makes with the normal at the point where incident ray strikes the mirror surface.

Further on reflection, it makes the same angle i.e. angle of reflection is equal to angle of reflection.

Hence, as angle of incidence is 55∘ angle of reflection too is 55∘ and the angle between the incident ray and the reflected ray is 55∘+55∘=110∘

Chris used a non-plane mirror to check out a box resting on a shelf, the focal length of the mirror is mathematically given as

f=8.38cm

Question Parameter(s):

The image of the box was located 15 cm behind the mirror

and the box was placed 19 cm from the mirror.

Generally, the equation for the focal length is mathematically given as

1/f=1/u+1/v

Therefore

1/f=1/15+1/19

f=8.3823529cm

In conclusion,  the focal length of the mirror

f=8.3823529cm

Read more about Lens

https://brainly.com/question/13161236

#SPJ2