Why earth have gravity

A machine part has the shape of a solid uniform sphere of mass 220 g and diameter 4.50 cm . It is spinning about a frictionless

miss Akunina [59]

Answer:

The angular acceleration is 10.10 rad/s².

Explanation:

Given that,

Mass of sphere =220 g

Diameter = 4.50 cm

Friction force = 0.0200 N

Suppose we need to find its angular acceleration.

We need to calculate the angular acceleration

Using formula of torque

$\tau=f\times r$

$I\times\alpha=f\times r$

Here, I = moment of inertia of sphere

$\dfrac{2}{5}mr^2\times\alpha=f\times r$

$\alpha=\dfrac{5\times f}{2mr}$

Put the value into the formula

$\alpha=\dfrac{5\times0.0200}{2\times220\times10^{-3}\times2.25\times10^{-2}}$

$\alpha=10.10\ rad/s^2$

Hence, The angular acceleration is 10.10 rad/s².

7 0

3 years ago

Why cant your rocket could never reach the speed of light?

Oksanka [162]

Answer:

The length of the object would shrink to zero which is not possible.

Explanation:

A rocket or any body cannot reach the speed of light because according to theory of relativity the and the Lorentz factor the length of the object would shrink to zero and the time dilation for that body would be infinite.

The Lorentz factor is given as:

$\gamma=\frac{1}{\sqrt{\frac{v^2}{c^2} } }$

where:

v = speed of the moving object

c = speed of light

4 0

3 years ago

What electrical force dies a Uranium nucleus exert on one of its inner electrons, located at a distance of 175 picometers (= 1.7

AlekseyPX

Answer:

correct option is d) 7.0 x 10^-7 N

Explanation:

given data

distance = 175 picometers = 1.75 × $10^{-10}$ m

to find out

electrical force

solution

we know atomic no of uranium is 92

and charge on electron is = 1.6 × $10^{-19}$ C

and electrical force is express as

electrical force = $\frac{1}{4 \pi \epsilon _o} \frac{q1q2}{r^2}$ .............1

put here value we get

electrical force = $9*10^9 \frac{92*(1.6*10^{-19})^2}{(1.75*10^{-10})^2}$

electrical force = 6.921 × $10^{-7}$ N

so correct option is d) 7.0 x 10^-7 N

5 0

3 years ago

Read 2 more answers

the hydrometer with the density of liquid to be 800 kg metre per square is the volume of the submerged part of the hydrometer is

julia-pushkina [17]

Answer:

Mass = 0.04 Kg

Explanation:

Given the following data;

Density = 800 kg/m³

Volume = 5 * 10^{-5} m³

To find the mass of the object;

Density can be defined as mass all over the volume of an object.

Simply stated, density is mass per unit volume of an object.

Mathematically, density is given by the formula;

$Density = \frac {mass}{volume}$

Making mass the subject of formula, we have;

$Mass = density * volume$

Substituting the values into the formula, we have;

$Mass = 800 * 5 * 10^{-5}$

Mass = 0.04 Kg

8 0

3 years ago

a battery of 5v and internal resistance of 5 ohms is connected to a resistor of 20 ohms. calculate the value of terminal voltage

Alborosie

Answer:

A bird flies 75m in 15s.Calculate its speed

7 0

2 years ago

Why earth have gravity​

Why earth have gravity