Show that for a projectile d2 (v2) / dt2 = 2g2

A car traveling 77 km/h slows down at a constant 0.48 m/s2 just by "letting up on the gas." A) Calculate the distance the car co

vfiekz [6]

Answer:

(a) 477 m

(b) 44.6 s

(c) 21.16 m

(d) 19.24 m

Explanation:

initial speed, u = 77km/h = 21.4 m/s

acceleration, a = - 0.48 m/s2

final speed v = 0

(a) let the stopping distance is s.

Use third equation of motion

$v^2 = u^2 + 2 a s\\\\0 = 21.4^2 - 2 \times 0.48\times s\\\\s = 477 m$

(b) Let t is time.

Use first equation of motion

v = u + at

0 = 21.4 - 0.48 t

t = 44.6 s

(c) Let the distance is s in first second.

Use second equation of motion

$s = u t + 0.5 at^2\\\\s = 21.4\times 1 - 0.5\times 0.48\times 1\\\\s = 21.4 - 0.24 = 21.16 m$

(d) distance traveled in 5 th second is given by

$s = u + 0.5 a (2 n - 1) \\\\s = 21.4 - 0.5\times 0.48 \times (2\times 5 -1)\\\\s= 21.4 - 2.16 = 19.24 m$

8 0

3 years ago

A laser beam of wavelength λ=632.8 nm shines at normal incidence on the reflective side of a compact disc. The tracks of tiny pi

anzhelika [568]

Answer:

The intensity of light be maximum is for angles 23.3° and 52.3°.

Explanation:

Given that,

Wave length = 632.8 nm

Distance = 1.60 μm

We need to calculate the intensity of light be maximum

Using Bragg's law

$d\sin\theta=n\lambda$

$\theta=\sin^{-1}(\dfrac{n\lambda}{d})$

We need to calculate the angle for different value of n

Using Bragg's law

$\theta=\sin^{-1}(\dfrac{n\lambda}{d})$

For n₁,

Put the value into the formula

$\theta=\sin^{-1}(\dfrac{632.8\times10^{-9}}{1.60\times10^{-6}})$

$\theta=23.3^{\circ}$

For n₂,

$\theta=\sin^{-1}(\dfrac{2\times632.8\times10^{-9}}{1.60\times10^{-6}})$

$\theta=52.3^{\circ}$

Hence, The intensity of light be maximum is for angles 23.3° and 52.3°.

6 0

3 years ago

Any fracture or system of fractures along which Earth moves is known as a

bogdanovich [222]

Any fracture or system of fractures along which Earth moves is known as a D.fault.

♡♡Hope I helped!!! :)♡♡

3 0

3 years ago

From the top of a cliff overlooking a lake, a person throws two stones. The two stones have identical initial speeds of v0 = 13.

Alina [70]

Answer:

X = 15.88 m

Explanation:

Given:

Initial Velocity V₀ = 13.4 m/s

θ = 30.1 °

g = 9.8 m/s²

To Find horizontal distance let "X" we have to time t first.

so from motion 2nd equation at Height h = 0

h = V₀y t + 1/2 (-g) t ² (ay = -g)

0 = 13.4 sin 30.1° t - 0.5 x 9.81 x t² (V₀y = V₀ Sin θ)

⇒ t = 1.37 s

Now For Horizontal distance X, ax =0m/s²

X = V₀x t + 1/2 (ax) t ²

X = 13.4 m × cos 30.1° x 1.37 s + 0

X = 15.88 m

8 0

4 years ago

What types of waves make up the electromagnetic spectrum?

vova2212 [387]

Gamma rays, x-rays, ultraviolet, infrared, microwaves and radio waves. Together with visible light, all these types of radiation make up what we call the electromagnetic spectrum

4 0

3 years ago

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