PLEASE PLEASE HELP<br> (Picture)

A man wishes to travel due north in order to cross a river 5 kilometers wide flowing due East at 3 kilometers per hour . if he c

Liono4ka [1.6K]

Answer:

17.46° W of N

Explanation:

His prow must point westward so that the westward component of his total velocity is equal to the eastward river speed.

3 = 10sinθ

sinθ = 3/10

θ = 17.4576... or about 17.46° W of N

it will take him 5 / 10cos17.46 = 0.52414... hrs. or about 31 min 27 s to cross.

7 0

3 years ago

The mass of a substance was found to be 8.2 g. By using the water displacement method the volume was found to be 3.6 cm3. Calcul

Vikki [24]

D= M/V

D=8.2/3.6

D= 2.3g/ml

5 0

4 years ago

Read 2 more answers

Which occurs when a wave is reflected?

dmitriy555 [2]

Answer: The wave can flip upside down.

Reflection is the bending of a wave when it cannot pass through. For example, plain mirrors which are flat, a ray of light hits the mirror and is reflected from the mirror since it cannot pass through

When reflection occurs the speed and frequency of the wave does not change but the wave is flipped upside down.

The speed does not change because speed is affected by the change in medium the frequency also remains the same since the energy of the wave does not change.

3 0

3 years ago

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What happens to the energy when the material is changed?

expeople1 [14]

Answer: When a material is heated or cooled, two changes may happen to the particles within the material: Chemical bonds between the particles may form, break or stretch. There is a change in the chemical potential store of energy in the material. The material will heat up or cool down as the particles within it gain or lose speed.

Explanation:

3 0

3 years ago

Astrology, that unlikely and vague pseudoscience, makes much of the position of the planets at the moment of one’s birth. The on

astraxan [27]

Answer: (a) $F=7(10)^{-7}N$

(b) $F=1.344(10)^{-6}N$

(c) The force of Jupiter on the baby is slightly greater than the the force of the father on the baby.

Explanation:

According to the law of universal gravitation, which is a classical physical law that describes the gravitational interaction between different bodies with mass:

$F=G\frac{m_{1}m_{2}}{r^2}$ (1)

Where:

$F$ is the module of the force exerted between both bodies

$G$ is the universal gravitation constant and its value is $6.674(10)^{-11}\frac{m^{3}}{kgs^{2}}$

$m_{1}$ and $m_{2}$ are the masses of both bodies.

$r$ is the distance between both bodies

Knowing this, let's begin with the answers:

<h2 /><h2>(a) Gravitational force Father exertes on baby</h2>

Using equation (1) and taking into account the mass of the father $m_{1}=100kg$ , the mass of the baby $m_{2}=4.20kg$ and the distance between them $r=0.2m$ , the force $F_{F}$ exerted by the father is:

$F_{F}=6.674(10)^{-11}\frac{m^{3}}{kgs^{2}}\frac{(100kg)(4.20kg)}{(0.2m)^2}$ (2)

$F_{F}=0.0000007N=7(10)^{-7}N$ (3)

<h2>(b) Gravitational force Jupiter exertes on baby</h2>

Using again equation (1) but this time taking into account the mass of Jupiter $m_{J}=1.898(10)^{27}kg$ , the mass of the baby $m_{2}=4.20kg$ and the distance between Jupiter and Earth (where the baby is) $r_{E}=6.29(10)^{11}m$ , the force $F_{J}$ exerted by the Jupiter is:

$F_{J}=6.674(10)^{-11}\frac{m^{3}}{kgs^{2}}\frac{(1.898(10)^{27}kg)(4.20kg)}{(6.29(10)^{11}m)^2}$ (4)

$F_{J}=0.000001344N=1.344(10)^{-6}N$ (5)

<h2>(c) Comparison</h2>

Now, comparing both forces:

$F_{J}=0.000001344N=1.344(10)^{-6}N$ and $F_{F}=0.0000007N=7(10)^{-7}N$ we can see $F_{J}$ is greater than $F_{F}$ . However, the difference is quite small as well as the force exerted on the baby.

7 0

3 years ago

PLEASE PLEASE HELP (Picture)