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2 years ago

Scientists have measured the distance between the Earth and the Moon by reflecting a beam of laser

Physics

1 answer:

FrozenT [24]2 years ago

5 0

Answer:

a)speed of light.

a)speed of light×time=distance.

Explanation:

light has a constant speed of 299,792,458m/s

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Which of the following is most likely to be an observation made by a physiologist

Naya [18.7K]

Do you have the answer choices ?

3 0

3 years ago

The radius of Saturn is about 10 times the radius of Venus and the mass is about 100 times that of Venus. How much larger is the

lora16 [44]

let the mass of Venus is M then mass of Saturn is 100 M

similarly if the radius of Venus is R then the radius of Saturn is 10 R

now the force of gravity on a man of mass "m" at the surface of Venus is given by

$F_1 = \frac{GMm}{R^2}$

now similarly the gravitational force on the man if he is at the surface of Saturn

$F_2 = \frac{G*100M*m}{(10R)^2}$

$F_2 = \frac{GMm}{R^2}$

so here if we divide the two forces

$\frac{F_1}{F_2} = 1$

so here we can say

F1 = F2

so on both planets the gravitational force will be same

7 0

3 years ago

What is the volume of an object that has Mass=100g and Density= 745g/mL.

lana66690 [7]

Answer:0.13ml

Explanation:

6 0

3 years ago

A square-based shipping crate is being designed that must contain a volume of 16 ft3 . The material that is used for the base an

Vlada [557]

Answer:

Explanation:

Given

volume $V=16 ft^3$

Suppose base is square with side L

height of crate is h

Volume $V=L^2\times h$

$16=L^2\times h$

Cost of top and bottom area $c_1=3L^2$

Cost of Side area $c_2=4Lh\times 2=8Lh=8L\times \frac{16}{L^2}=\frac{128}{L}$

Total Cost $C=c_1+c_2$

Total Cost $C=3L^2+\frac{128}{L}$

Differentiate C w.r.t Length

$\frac{dC}{dL}=6L-\frac{128}{L^2}$

$L^3=\frac{128}{6}$

$L=2.75 ft$

$h=\frac{16}{2.75^2}=11.46 ft$

Dimensions are $L\times L\times h=2.75\times 2.75\times 11.46$

6 0

2 years ago

Problem 3.

Korolek [52]

Answer:

143.352 watt.

Explanation:

So, in the question above we are given the following parameters or data or information that is going to assist us in answering the question above efficiently. The parameters are:

"A 1.8 m wide by 1.0 m tall by 0.65m deep home freezer is insulated with 5.0cm thick Styrofoam insulation"

The inside temperature of the freezer = -20°C.

Thickness = 5.0cm = 5.0 × 10^-2 m.

Step one: Calculate the surface area of the freezer. That can be done by using the formula below:

Area = 2[ ( Length × breadth) + (breadth × height) + (length × height) ].

Area = 2[ (1.8 × 0.65) + (0.65 × 1.0) + (1.8 × 1.0)].

Area = 7.24 m^2.

Step two: Calculate the rate of heat transfer by using the formula below;

Rate of heat transfer =[ thermal conductivity × Area (T1 - T2) ]/ thickness.

Rate of heat transfer = 0.022 × 7.24(25+20)/5.0 × 10^-2 = 143.352 watt.

8 0

3 years ago