All categories

3 years ago

What happens when all the external forces on a system are balanced ?

1 answer:

5 0

Equilibrium refers to a state in which all of the external forces on an object all balance each other such that there is no net effect (net force equals 0). An object in equilibrium will not experience acceleration, and will either remain at rest, or continue moving at a constant velocity. Here's a simple example, pick up a book (or any random object) and hold it up in the air. The book is now in equilibrium, the downwards force of gravity is perfectly countered by the upwards force that you are applying to it. Notice that the object neither falls nor goes upwards (i.e. no acceleration). Now let go of the book, notice how it falls downwards till it hits the ground (or whatever was beneath it). That is because without the upwards force applied by your hand, the object is no longer in equilibrium, and the force of gravity takes over until it is in equilibrium again.

You might be interested in

Types of polarization physics

Sidana [21]

Answer:

Linear polarization.

Circular polarization.

Elliptical polarization.

8 0

2 years ago

Approximately, What is the value of the Hubble Constant, as measured by scientists? Hypothetically, if the value of the Hubble C

Serhud [2]

Answer:

The current value of the Hubble's constant = 73 km/sec/Mpc.

t = 71.9 trillion years will be the new age of universe if the Hubble constant = 700 km/s/Mpc

Explanation:

The current value of the Hubble's constant = 73 km/sec/Mpc. However, recent discoveries in the cosmology contradicts the idea of Hubble constant as being fixed. Some scientists are not agreeing on this value and the debate is going on.

Hubble law states that how fast universe is expanding or in other words, galaxies are expanding separating with a speed directly proportional to the distance of galaxies to the earth.

Hence,

v is directly proportional to d

where, v = apparent velocity

d = distance

if we equate velocity and distance then there comes Hubble constant.

v = $H_{0}$ x d

$H_{0}$ = 73 km/sec/Mpc

where, Mpc = Mega Parsec = 1 Mpc = 3.086 x $10^{19}$ km

We can use Hubble constant to tell the age of universe.

t = d/v

t = d/( $H_{0}$ xd)

t = 1/ $H_{0}$

Scientist calculated the age of universe by using Hubble constant, which is 13.4 billion years.

Now, if we hypothetically change the value of Hubble constant,

from $H_{0}$ = 73 km/sec/Mpc to $H_{0}$ = 700 km/sec/Mpc

then the age of universe will be:

t = 1/ $H_{0}$

first convert the units of new $H_{0}$ into 1/s

$H_{0}$ = (700) x (/3.08 x $10^{19}$ )

$H_{0}$ = 227.27 x $10^{-19}$ = 2.27 x $10^{-21}$ 1/s

So,

Age of universe will be:

t = 1/ $H_{0}$ = 1/2.27x $10^{-21}$ 1/s

t = 2.27 x $10^{21}$ s

t = 71.9 trillion years

t = 71.9 trillion years will be the new age of universe if the Hubble constant = 700 km/s/Mpc

6 0

2 years ago

a wagon of mass 42 kg is pushed by a student a distance of 12.2 meters, and 297 j of work was sone on the wagon how much force d

a_sh-v [17]

Answer:

Force=2.484 N

Explanation:

$f = \frac{w}{gh} \\ = \frac{297}{9.8 \times 12.2} \\ f = 2.484 \: n$

Hope it helped

PLS mark BRAINLIEST

8 0

3 years ago

What is a good example of a contact force?

exis [7]

Answer:

Sitting on a couch

Explanation:

The couch is exerting an upwards force so that would make it a contact force

5 0

3 years ago

What is the potential difference across one wire of a 70 m extension cord made of 16 gauge copper wire carrying a current of 4 A

Butoxors [25]

Answer:

V = 3.6 volts

Explanation:

From Ohm's Law, we know that:

V = IR

but,

R = ρL/A

Therefore,

V = IρL/A

where,

V = Potential Difference = ?

I = Current = 4 A

ρ = resistivity of copper = 1.68 x 10⁻⁸ Ω.m

L = Length = 70 m

A = Cross-sectional Area = πd²/4 = π(1.29 x 10⁻³ m)²/4 [16 gauge wire has a diameter of 1.29 mm]

A = 1.31 x 10⁻⁶ m²

V = (4 A)(1.68 x 10⁻⁸ Ω.m)(70 m)/(1.31 x 10⁻⁶ m²)

<u>V = 3.6 volts</u>

3 0

3 years ago