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3 years ago

A coin dropped from the top of a precipice (cliff) takes 2.42 to hit the ground. How highis the precipice (cliff)? .

Physics

1 answer:

goldfiish [28.3K]3 years ago

4 0

Answer:

28.7 m.

Explanation:

Hello,

In this case, since the coin is dropped from the rest condition at which the initial velocity is 0 m/s, we can compute the height of the precipice via the following equation:

$y=y_0+v_0*t-\frac{1}{2}gt^2$

Whereas the final height is 0, the initial one is to be computed and the gravity is considered as 9.8 m/s², therefore the height turns out:

$y=y_0+v_0*t-\frac{1}{2}gt^2\\\\y_0=\frac{1}{2}gt^2=\frac{1}{2}*9.8m/s^2*(2.42s)^2 \\\\y_0=28.7m$

It means that the height of the cliff is 28.7 m.

Regards.

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You have three objects of varying shapes and sizes: Object 1 is a rectangular block of tin. Object 2 is a cube of aluminum. Obje

Over [174]

Answer: a. m = 7.7 kg

b. V = 435.52 in³

c. m = 1927 kg

d. V = 335.37 cm³

e. m = 3 kg

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The formula for density is

$\rho=\frac{m}{V}$

Density's unit in SI is kg/m³, but it can assume lots of other units.

Some unit transformations necessary for the resolution of the question:

1 L = 1 dm³ = 1000 cm³

1 in³ = 16.3871 cm³

1 g = 0.001 kg

a. V = 1.34 L = 1340 cm³

$\rho=\frac{m}{V}$

$m=\rho.V$

m = 5.75 * 1340

m = 7705 g => 7.705 kg

Mass of object 1 with volume 1.34L is 7.7 kg.

b. A cube's volume is calculated as V = side³

V = 7.58³

V = 435.52 in³

Volume of object 2 is 435.52 in³.

c. Using 1 in³ = 16.3871 cm³ to change units:

V = 435.52 * 16.3871

V = 713689.4 cm³

Then, mass will be

$m=\rho.V$

m = 2.7 * 713689.4

m = 1926961.4 g => 1927 kg

Mass of object 2 is 1927 kg.

d. Volume of a sphere is calculated as $V=\frac{4}{3}.\pi.r^{3}$

Diameter is twice the radius, then r = 4.31 cm.

Volume is

$V=\frac{4}{3}.\pi.(4.31)^{3}$

V = 335.37 cm³

Volume of object 3 is 335.37 cm³.

e. $m=\rho.V$

m = 8.96 * 335.37

m = 3004.91 g => 3 kg

Mass of object 3 is 3 kg.

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3 years ago

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Explanation:

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2 years ago

A 2 kg ball is moving 3 m/s when it starts rolling up a hill.

AURORKA [14]

Answer:

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Explanation:

We need to make a sketch of the ball and see the location of the reference point where the potential energy is zero. But the kinetic energy will be defined by the following expression:

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