A ball is thrown downward at 4.5 m/s and accelerates at 9.8 m/s^2. What is its instantaneous velocity 2.4 s later?

Hooke's law describes a certain light spring of unstretched length 31.8 cm. when one end is attached to the top of a doorframe a

lubasha [3.4K]

Answer:

Explanation:

extension in the spring = 40.4 - 31.8 = 8.6 cm = 8.6 x 10⁻² m .

kx = mg

k is spring constant , x is extension , m is mass

k x 8.6 x 10⁻² = 7.52 x 9.8

k = 856.93 N/m

= 857 x 10⁻³ KN /m

b ) Both side is pulled by force of 188 N .

Tension in spring = 188N

kx = T

856.93 x = 188

x = .219.38 m

= 21.938 cm

= 21.9 cm .

length of spring = 31.8 + 21.9

= 53.7 cm .

6 0

2 years ago

Luis and Aisha conducted an experiment. They exerted different forces on four objects. Their results are shown in the table.

lesya692 [45]

Answer:

Object 3 has greatest acceleration.

Explanation:

Objects Mass Force

1 10 kg 4 N

2 100 grams 20 N

3 10 grams 4 N

4 1 kg 20 N

Acceleration of object 1,

$a_1=\dfrac{F_1}{m_1}\\\\a_1=\dfrac{4}{10}\\\\a_1=0.4\ m/s^2$

Acceleration of object 2,

$a_2=\dfrac{F_2}{m_2}\\\\a_2=\dfrac{20}{0.1}\\\\a_2=200\ m/s^2$

Acceleration of object 3,

$a_3=\dfrac{F_3}{m_3}\\\\a_3=\dfrac{4}{0.01}\\\\a_3=400\ m/s^2$

Acceleration of object 4,

$a_4=\dfrac{F_4}{m_4}\\\\a_4=\dfrac{20}{1}\\\\a_3=20\ m/s^2$

It is clear that the acceleration of object 3 is $400\ m/s^2$ and it is greatest of all. So, the correct option is (3).

4 0

3 years ago

Read 2 more answers

The acceleration reaches its minimal value of zero at the top of the trajectory. *

Serhud [2]

it is true. the trajectory reaches the value of zero at the top

4 0

3 years ago

When waves superimpose and make bigger amplitudes what form of interference is that

eimsori [14]

Answer:

Constructive Interference

Explanation:

Constructive Interference occurs when two waves superimpose and make bigger amplitudes.

In constructive interference, the crests of one wave fall on the crests of second wave and the amplitudes add up. The amplitude of the resultant wave is equal to sum of the amplitude of the individual waves. Similarly, the trough of first wave falls on the trough of other wave and they superimpose to create the trough of the resultant wave.

For Example, In the attachment, two waves A and B superimpose and demonstrate Constructive interference to create the wave C.

7 0

3 years ago

Raindrops hitting the side windows of a car in motion often leave diagonal streaks even if there is no wind. Why? Is the explana

labwork [276]

Answer:

because of the raindrop velocity relative of the car has a vertical and horizontal component

Explanation:

The car moves in a <em>horizontal direction </em>relative to the ground. The raindrops fall in the <em>vertical direction</em> relative to the ground.
Their velocity relative to the moving car has both vertical and horizontal components and this is the reason for the diagonal streaks on the side window.
The diagonal streaks on the windshield arise from a different reason.
The drops are pushed off to one side of the windshield because of air resistance.

6 0

2 years ago

A ball is thrown downward at 4.5 m/s and accelerates at 9.8 m/s^2. What is its instantaneous velocity 2.4 s later?​

A ball is thrown downward at 4.5 m/s and accelerates at 9.8 m/s^2. What is its instantaneous velocity 2.4 s later?