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4 years ago

A subtence floats or sinks in onother becauseof its relitivity

1 answer:

3 0

No. A substance floats or sinks in another substance because of
the densities of both of them.

If the density of the substance is more than the density of the other
one, it will sink. If less than the density of the other one, it will float.

You might be interested in

Calculate the magnitude of the focal length and power of a spherical mirror that has a radius of 5.00 cm.

yarga [219]

Answer:

2.5 cm

40 D

Explanation:

When the radius of curvature of a lens is divided by 2 we get the focal length of the lens.

Focal length is given by

$f=\dfrac{R}{2}\\\Rightarrow f=\dfrac{5}{2}\\\Rightarrow f=2.5\ cm$

The focal length of the lens is 2.5 cm

When we divide 1 by the focal length in the unit of meters we get the power of a lens

Power of a lens is given by

$P=\dfrac{1}{f}\\\Rightarrow P=\dfrac{1}{0.025}\\\Rightarrow P=40\ D$

The power of the lens is 40 D

5 0

4 years ago

The reaction energy of a reaction is the amount of energy released by the reaction. It is found by determining the difference in

solmaris [256]

Answer: the correct answer is 7.8026035971 x 10^(-13) joule

Explanation:

Use Energy Conservation. By ``alpha decay converts'', we mean that the parent particle turns into an alpha particle and daughter particles. Adding the mass of the alpha and daughter radon, we get

m = 4.00260 u + 222.01757 u = 226.02017 u .

The parent had a mass of 226.02540 u, so clearly some mass has gone somewhere. The amount of the missing mass is

Delta m = 226.02540 u - 226.02017 u = 0.00523 u ,

which is equivalent to an energy change of

Delta E = (0.00523 u)*(931.5MeV/1u)

Delta E = 4.87 MeV

Converting 4.87 MeV to Joules

1 joule [J] = 6241506363094 mega-electrón voltio [MeV]

4 mega-electrón voltio = 6.40870932 x 10^(-13) joule

4.87 mega-electrón voltio = 7.8026035971 x 10^(-13) joule

5 0

4 years ago

A 50g ball is released from rest 1.0 above the bottom of thetrack

ludmilkaskok [199]

Answer:

The maximum height of the ball is 2 m.

Explanation:

Given that,

Mass of ball = 50 g

Height = 1.0 m

Angle = 30°

The equation is

$y=\dfrac{1}{4}x^2$

We need to calculate the velocity

Using conservation of energy

$\Delta U_{i}+\Delta K_{i}=\Delta K_{f}+\Delta U_{f}$

Here, ball at rest so initial kinetic energy is zero and at the bottom the potential energy is zero

$\Delta U_{i}=\Delta K_{f}$

Put the value into the formula

$mgh=\dfrac{1}{2}mv^2$

Put the value into the formula

$50\times10^{-3}\times9.8\times1.0=\dfrac{1}{2}\times50\times10^{-3}\times v^2$

$v^2=\dfrac{2\times50\times10^{-3}\times9.8\times1.0}{50\times10^{-3}}$

$v=\sqrt{19.6}$

$v=4.42\ m/s$

We need to calculate the maximum height of the ball

Using again conservation of energy

$\dfrac{1}{2}mv^2=mgh$

Here, h = y highest point

Put the value into the formula

$\dfrac{1}{2}\times50\times10^{-3}\times(4.42)^2=50\times10^{-3}\times9.8\times h$

$y=\dfrac{0.5\times(4.42)^2}{9.8}$

$y=0.996\ m$

Put the value of y in the given equation

$y=\dfrac{1}{4}x^2$

$x^2=4\times0.996$

$x=\sqrt{4\times0.996}$

$x=1.99\ m\ \approx 2 m$

Hence, The maximum height of the ball is 2 m.

4 0

3 years ago

1. What is work done in holding a 15kg suitcase while waiting for a bus for 15 minutes?

Tems11 [23]

Work is (force applied) x (distance through which the force moves).

Since the suitcase doesn't move up or down during the 15 minutes,
no work is done ... zero, zip, nada ... according to the real Physics
definition of 'work'.

6 0

3 years ago

a car is travelig at 20.0 m/s when the driver applies the brakes and comes to a stop. if the car slows down uniformly with an ac

alisha [4.7K]

Since acceleration is constant, we can use the formula

v² - u² = 2a ∆x

where v = final velocity, u = initial velocity, a = acceleration, and ∆x = displacement. Then

0² - (20.0 m/s)² = 2 (-4.20 m/s²) ∆x

⇒ ∆x = (20.0 m/s)² / (8.40 m/s²) ≈ 47.6 m

3 0

3 years ago