All categories

3 years ago

A freely falling object is dropped from rest, what is its speed after falling 1 second? 2 seconds? 3 seconds? 10 seconds?

Physics

1 answer:

SSSSS [86.1K]3 years ago

6 0

Answer:

You can use the formula: X= Vinitial.t + $\frac{1}{2}$ g $t^{2}$

where: X: distance, which the question wants.

V initial = Zero

t= 1,2,3,10 sec.

g: is the acceleration due to gravity = 9.8 m/ $s^{2}$

You might be interested in

The position of an object is given by the equation x = 4.0t2 - 2.0 t - 4.5where x is in meters and t is in seconds. What is the

s344n2d4d5 [400]

Answer:

Explanation:

x = 4 t^2 - 2 t - 4.5

Position at t = 3 s

x = 4 (3)^2 - 2 (3) - 4.5 = 25.5 m

Velocity at t = 3 s

v = dx / dt = 8 t - 2

v ( t = 3 s) = 8 x 3 - 2 = 22 m/s

Acceleration at t = 3 s

a = dv / dt = 8

a ( t = 3 s ) = 8 m/s^2

When is the velocity = 0

v = 0

8 t - 2 = 0

t = 0.25 second

When is the position = 0

x = 0

4 t^2 - 2 t - 4.5 = 0

$t = \frac{2 \pm \sqrt{4 + 72}}{8}$

t = 1.4 second

8 0

3 years ago

The amount of charge that passes through the filament of a certain lightbulb in 2.00 s is 1.67 C. If the current is supplied by

Artemon [7]

Answer:

E = 20.03 J

Explanation:

Given that,

The amount of charge that passes through the filament of a certain lightbulb in 2.00 s is 1.67 C,

Voltage, V = 12 V

We need to find the energy delivered to the lightbulb filament during 2.00 s.

The energy delivered is given by :

$E=I^2Rt$ . ....(1)

As,

$I=\dfrac{q}{t}\\\\I=\dfrac{1.67}{2}\\\\I=0.835\ A$

As per Ohm's law, V = IR

$R=\dfrac{V}{I}\\\\R=\dfrac{12}{0.835}\\\\R=14.37\ \Omega$

Using formula (1).

$E=0.835^2\times 14.37\times 2\\\\=20.03\ J$

So, the energy delivered to the lightbulb filament is 20.03 J.

6 0

3 years ago

A)If the rms value of the electric field in an electromagnetic wave is doubled, by what factor does the rms value of the magneti

Ghella [55]

A) The magnetic field doubles as well

The relationship between rms value of the electric field and rms value of the magnetic field for an electromagnetic wave is the following:

$E_{rms}=cB_{rms}$

where

E_rms is the magnitude of the electric field

c is the speed of light

B_rms is the magnitude of the magnetic field

From the equation, we see that the electric field and the magnetic field are directly proportional: therefore, if the rms value of the electric field is doubled, then the rms value of the magnetic field will double as well.

B) The intensity will quadruple

The intensity of an electromagnetic wave is given by

$I=\frac{1}{2}c\epsilon_0 E_0^2$

where

c is the speed of light

$\epsilon_0$ is the vacuum permittivity

$E_0$ is the peak intensity of the electric field

The rms value of the electric field is related to the peak value by

$E_{rms}=\frac{E_0}{\sqrt{2}}$

So we can rewrite the equation for the intensity as

$I=c\epsilon_0 E_{rms}^2$

we see that the intensity is proportional to the square of the rms value of the electric field: therefore, if the rms value of the electric field is doubled, the average intensity of the wave will quadruple.

7 0

3 years ago

Andrea and the other members of the tennis team are practicing hitting tennis balls. If two people hit identical balls at the sa

Pachacha [2.7K]

If two people hit identical tennis balls at the same time, the ball that has the most kinetic energy is the ball that moves at the fastest speed.

<u>Explanation:</u>

The energy possessed by an object by virtue of its motion is called its kinetic energy indicating that only moving objects have kinetic energy. The kinetic energy of an object depends on its speed and mass.

It is given by the expression

$K=1/2 mv^2$

where m denotes the mass of the object and v denotes its velocity.

since kinetic energy is directly proportional to the square of the velocity, the kinetic energy of an object increases with its velocity.

Hence an object that moves at the fastest speed will have the most kinetic energy.

8 0

3 years ago

Compared with those who live in the lowlands, people who live in the Southeast highlands experience

Alisiya [41]

Answer:

The territory of Scotland was divided into two parts -- the highlands and the lowlands.

Explanation:

The people living in places of high altitudes are called highlanders. These high altitude places are called high lands and places with low elevations or altitudes are called the low lands. There are many differences between the two places and people experiences different difficulties in these places.

Some of the differences are :

The life of the people living in high lands are much more tougher than those living in the low lands. The highlanders have to work more hard than lowlanders.

The agricultural activities are more flourished in the low lands than in the high lands.

The low lands are more populated and highly industrialized than the high lands. Iron and steel industry, metal working industry and agriculture are some of the main industries of lowlands. They are the land of the Scottish nation.

6 0

3 years ago