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3 years ago

13

The driver of a car slams on the brakes when he sees a tree blocking the road. The car slows uniformly with acceleration of -5.7

5 m/s^2 for 4.40 s, making straight skid marks 60.0 m long, all the way to the tree. With what speed does the car then strike the tree? m/s

1 answer:

Furkat [3]3 years ago

3 0

Answer:

0.99 m/s

Explanation:

t = Time taken = 4.4 seconds

u = Initial velocity

v = Final velocity

s = Displacement = 60 m

a = Acceleration = -5.75 m/s²

$s=ut+\frac{1}{2}at^2\\\Rightarrow u=\frac{s-\frac{1}{2}at^2}{t}\\\Rightarrow u=\frac{60-\frac{1}{2}\times -5.75\times 4.4^2}{4.4}\\\Rightarrow u=26.29\ m/s$

$v=u+at\\\Rightarrow v=26.29+(-5.75)\times 4.4\\\Rightarrow v=0.99\ m/s$

The car hits the tree at 0.99 m/s

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If you walk a distance of 8 blocks and then 3 blocks south from home, what is your position compared to home? What distance did

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The position compared to that of home is a reference to displacement, I believe.

Displacement = x total - x initial

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3 years ago

Jaden has a mass of 45 kilograms on Earth. Jupiter has more gravity than the Earth. On Jupiter, Jaden's mass will be O more than

Dovator [93]

Answer:

m = 45 kg

Explanation:

Given that,

Mass of Jadan, m = 45 kg on Earth

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3 years ago

WGVU-AM is a radio station that serves the Grand Rapids, Michigan area. The main broadcast frequency is 1480kHz. At a certain di

Yuki888 [10]

Answer:

a

$\lambda = 202.7 \ m$

b

$w = 9.3 *10^{6} \ rad/s$

c

$k = 0.031 m^{-1}$

d

$E_{max} = 9.0 *10^{-3} \ V/m$

Explanation:

From the question we are told that

The frequency of the radio station is $f= 1480 \ kHz = 1480 *10^{3}\ Hz$

The magnitude of the magnetic field is $B = 3.0* 10^{-11} \ T$

Generally the wavelength is mathematically represented as

$\lambda = \frac{c}{f}$

Here c is the speed of light with value $c = 3.0 *10^{8} \ m/s$

So

$\lambda = \frac{3.0 *10^{8}}{ 1480 *10^{3}}$

=> $\lambda = 202.7 \ m$

Generally the angular frequency is mathematically represented as

$w = 2 \pi * f$

=> $w = 2 * 3.142 * 1480 *10^{3}$

=> $w = 9.3 *10^{6} \ rad/s$

Generally the wave number is mathematically represented as

=> $k = \frac{2 \pi }{\lambda}$

=> $k = \frac{2 * 3.142 }{ 202.7}$

=> $k = 0.031 m^{-1}$

Generally the amplitude of the electric field at this distance from the transmitter is mathematically represented as

$E_{max} = c * B$

=> $E_{max} = 3.0 *10^{8} * 3.0* 10^{-11}$

=> $E_{max} = 9.0 *10^{-3} \ V/m$

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3 years ago

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NemiM [27]

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A pulley is a wheel on an axle or shaft that is created to support movement, it makes carry loads easier.

A pulley is a simple type of machine, which in the above explained case makes carrying a load easier.

4 0

3 years ago

An infinite line of charge with charge density λ1 = 0.6 μC/cm is aligned with the y-axis.

Ganezh [65]

Answer:

1440 × 10⁴ N/C

Explanation:

Data provided in the question:

Charge density λ1 = 0.6 μC/cm = 6 × 10⁻⁵ C/m

a = 7.5 cm = 0.075 m

Now,

Electric field due to a line charge at a distance 'a' is given as:

Ex(P) = $\frac{\lambda}{2\pi\epsilon_0a}$

also,

we know

$\frac{1}{4\pi\epsilon_0}$ = 9 × 10⁹ Nm²/C²

Thus,

we have

Ex(P) = $\frac{2}{2}\times\frac{\lambda}{2\pi\epsilon_0a}=\frac{2\lambda}{4\pi\epsilon_0a}$

therefore,

Ex(P) = $\frac{2\times6\times10^{-5}\times9\times10^9}{0.075}$

= 1440 × 10⁴ N/C

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4 years ago