1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
MrRa [10]
3 years ago
7

Hi guys. Help with any of these questions! Pressure in physics year 7 :) Thanks!

Physics
1 answer:
SVEN [57.7K]3 years ago
5 0

Answer:

2 a) it is less dense than the water

2 b) it is more dense than the water

3 a ping pong ball is hollow and less dense than the water so it quickly bounces up to the surface of the water

You might be interested in
A mass free to vibrate on a level, frictionless surface at the end of a horizontal spring is pulled 35 cm from its equilibrium p
saul85 [17]

Answer:

0.67 s

Explanation:

This is a simple harmonic motion (SHM).

The displacement, x, of an SHM is given by

x = A\cos(\omega t)

A is the amplitude and \omega is the angular frequency.

We could use a sine function, in which case we will include a phase angle, to indicate that the oscillation began from a non-equilibrium point. We are using the cosine function for this particular case because the oscillation began from an extreme end, which is one-quarter of a single oscillation, when measured from the equilibrium point. One-quarter of an oscillation corresponds to a phase angle of 90° or \frac{\pi}{4} radian.

From trigonometry, \sin A =\cos B if A and B are complementary.

At t = 0, x = 3.5

3.5 = A\cos(\omega \times0)

A =3.5

So

x = 3.5\cos(\omega t)

At t = 0.12, x = 1.5

1.5 = 3.5\cos(0.12\omega)

\cos(0.12\omega)=\dfrac{1.5}{3.5}=0.4286

0.12\omega =\cos^{-1}0.4286

0.12\omega = 1.13

\omega = 9.4

The period, T, is related to \omega by

T = \dfrac{2\pi}{\omega} = \dfrac{2\times3.14}{9.4}=0.67

5 0
3 years ago
1) Calculate the potential energy of a 5.00 kg object sitting on a 3.00 meter high ledge.
maria [59]

Answer:

15kg

Explanation:

5 0
3 years ago
Plane-polarized light is incident on a single polarizing disk, with the direction of E0 parallel to the direction of the transmi
Vladimir [108]

Answer: 65.9^{\circ}

Explanation:

Given

Intensity must be reduced by a factor of 6

Intensity is given by I=I_o\cos ^2\theta\\

Substitute I by \frac{I_o}{6}

\Rightarrow \dfrac{I_o}{6}=I_o\cos ^2\theta\\\\\Rightarrow \cos^2\theta =\dfrac{1}{6}\\\\\Rightarrow \cos \theta=\dfrac{1}{\sqrt{6}}\\\\\Rightarrow \theta=65.9^{\circ}

So, the disk must be rotated by an angle of 65.9^{\circ} .

7 0
2 years ago
What happens to the gravitational force between two masses when the distance between the masses is doubled?
vovangra [49]

Answer:

It decreases by a factor of 4

Explanation:

The gravitational force between two masses is given by

F=\frac{Gm_1 m_2}{r^2}

where

G is the gravitational constant

m1, m2 are the two masses

r is the separation between the two masses

In this problem, the distance between the masses is doubled, so

r' = 2r

Substituting into the equation, we see that the new force is

F'=\frac{Gm_1 m_2}{(2r)^2}=\frac{1}{4}\frac{Gm_1m_2}{r^2})\frac{F}{4}

So, the force decreases by a factor of 4.

6 0
3 years ago
A charge Q is placed on the x axis at x = +4.0 m. A second charge q is located at the origin. If Q = +75 nC and q = −8.0 nC, wha
Stells [14]

Answer:

23.1 N/C

Explanation:

OP = 3 m , OQ = 4 m

PQ = \sqrt{4^{2}+3^{2}}=5 m

q = - 8 nC, Q = 75 nC

Electric field at P due to the charge Q is

E_{1}=\frac{KQ}{PQ^{2}}=\frac{9\times 10^{9}\times 75\times 10^{-9}}{25}=27 N/C

Electric field at P due to the charge q is

E_{2}=\frac{Kq}{PO^{2}}=\frac{9\times 10^{9}\times 8\times 10^{-9}}{9}=8 N/C

According to the diagram, tanθ = 3/4

Resolve the components of E1 along x axis and along y axis.

So, Electric field along X axis, Ex = - E1 Cos θ

Ex = - 27 x 4 / 5 = - 21.6 N/C

Electric field along y axis, Ey = E1 Sinθ - E2

Ey = 27 x 3 /5 - 8 = 8.2 N/C

The resultant electric field at P is given by

E=\sqrt{E_{x}^{2}+E_{y}^{2}}=\sqrt{(-21.6)^{2}+(8.2)^{2}}=23.1 N/C

3 0
3 years ago
Other questions:
  • A common characteristic of mountains formed by two colliding continents is marine _______ rock. A. sedimentary B. limestone C. i
    7·1 answer
  • A 1280 kg car is moving 4.92 m/s. a 509 N force then pushes it forward for 28.7 m. what is its final KE?(unit=J)PLEASE HELP
    5·2 answers
  • Sleep is a difficult problem for dolphins because dolphins __________. A. need more sleep than their predators B. must be awake
    5·2 answers
  • The force behind electron movement is called <br>A. voltage B. current C. resistance D. ohm​
    11·1 answer
  • What is numbers 2 and 4? Please help, and many thanks to those who do chose to help.
    13·1 answer
  • A firecracker in a coconut blows the coconut into three pieces. Twopieces of equal mass fly off south and west, perpendicular to
    7·1 answer
  • 3 write the three laws given by kepler.How did they help Newton to arrive at the inverse square law of gravity?​
    13·1 answer
  • Why is it not possible to make use of solar cells to meet all of our energy needs?why​
    8·2 answers
  • The block in the figure below has a mass of 5.1 kg and it rests on an incline of angle . You pull on the rope with a force F = 3
    10·1 answer
  • The diagram above shows a metal disk of weight 1.0 N resting on an index card that is balanced on top of a glass. What is the no
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!