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3 years ago

I need help with these Physics problems

Physics

1 answer:

adoni [48]3 years ago

4 0

Answer:

1. 3 m

2. 27 s

Explanation:

1. "A car traveling at +33 m/s sees a red light and has to stop. If the driver can accelerate at -5.5 m/s², how far does it travel?"

Given:

v₀ = 33 m/s

v = 0 m/s

a = -5.5 m/s²

Unknown: Δx

To determine the equation you need, look for which variable you don't have and aren't solving for. In this case, we aren't given time and aren't solving for time. So look for an equation that doesn't have t in it.

Equation: v² = v₀² + 2aΔx

Substitute and solve:

(0 m/s)² = (33 m/s)² + 2(-5.5 m/s²) Δx

Δx = 3 m

2. "A plane starting from rest at one end of a runway accelerates at 4.8 m/s² for 1800 m. How long did it take to accelerate?"

Given:

v₀ = 0 m/s

a = 4.8 m/s²

Δx = 1800 m

Unknown: t

Equation: Δx = v₀ t + ½ a t²

Substitute and solve:

1800 m = (0 m/s) t + ½ (4.8 m/s²) t²

t ≈ 27 s

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Suppose that on a hot and sticky afternoon in the spring, a tornado passes over the high school. If the air pressure in the lab

forsale [732]

Answer:

232.9m³ (Option b. is the closest answer)

Explanation:

Given:

Air pressure in the lab before the storm, P₁ = 1.1atm

Air volume in the lab before the storm, V₁ = 180m³

Air pressure in the lab during the storm P₂ = 0.85atm

Air volume in the lab before the storm, V₂ = ?

Applying Boyle's law: P₁V₁ = P₂V₂ (at constant temperature)

$V_{2} = \frac{P_{1}V_{1}}{P_{2}}$

$V_{2} = \frac{1.1 * 180}{0.85}$

$V_{2} = \frac{198}{0.85}$

V₂ = 232.9m³

The air volume in the laboratory that would expand in order to make up for the large pressure difference outside is 232.9m³

7 0

3 years ago

In a physics lab, light with a wavelength of 570 travels in air from a laser to a photocell in a time of 16.5 . When a slab of g

aliina [53]

Answer:

Wavelength is calculated as 213.9 nm

Solution:

As per the question:

Wavelength of light = 570 nm

Time, t = 16.5 ns

Thickness of glass slab, d = 0.865 ns

Time taken to travel from laser to the photocell, t' = 21.3

Speed of light in vacuum, c = $3\times 10^{8}\ m/s$

Now,

To calculate the wavelength of light inside the glass:

After the insertion of the glass slab into the beam, the extra time taken by light to cover a thickness t = 0.865 m is:

t' - t = 21.3 - 16.5 = 4.8 ns

Thus

$\frac{d}{\frac{c}{n}} - \frac{d}{v} = 4.8\times 10^{- 9}$

$\frac{0.8656}{\frac{c}{n}} - \frac{0.865}{v} = 4.8\times 10^{- 9}$

where

n = refractive index of the medium

v = speed of light in medium

$\frac{0.8656}{\frac{c}{n}} - \frac{0.865}{v} = 4.8\times 10^{- 9}$

$n = \frac{4.8\times 10^{- 9}\times 3.00\times 10^{8}}{0.865} + 1$

n = 2.66

Now,

The wavelength in the glass:

$\lambda' = \frac{\lambda }{n}$

$\lambda' = \frac{570}{2.66} = 213.9\ nm$

5 0

3 years ago

Please help me with my quiz?

alina1380 [7]

The solutions would be :
1. C
2. B
3. A
4. C
5. D.

3 0

3 years ago

The 59 converted into binary is _____.<br> How do we convert number to binary?

Viefleur [7K]

Answer:

111011

Explanation:

59/2 = 29, remainder is 1

29/2 = 14, remainder is 1

14/2 = 7, remainder is 0

7/2 = 3, remainder is 1

3/2 = 1, remainder is 1

1/2 = 0, remainder is 1

8 0

3 years ago

Which star has the highest surface temperature?

lesya [120]

Answer:

white star

Explanation:

because it is the hottest form of a star

7 0

2 years ago

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I need help with these Physics problems​

I need help with these Physics problems