What is the heaviest planet in the worlx

If the velocity of an object is zero at one instant, what is true about the acceleration of that object

Charra [1.4K]

Answer:

I. The acceleration could be positive.

II. The acceleration could be zero.

III. The acceleration could be negative.

Explanation:

Velocity can be defined as the rate of change in displacement (distance) with time. Velocity is a vector quantity and as such it has both magnitude and direction.

Mathematically, velocity is given by the equation;

$Velocity = \frac{distance}{time}$

If the velocity of an object is zero at one instant, then the acceleration of that object may have the following characteristics;

I. The acceleration could be positive.

II. The acceleration could be zero.

III. The acceleration could be negative.

In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.

This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.

Mathematically, acceleration is given by the equation;

$Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}$

$a = \frac{v - u}{t}$

Where,

a is acceleration measured in $ms^{-2}$

v and u is final and initial velocity respectively, measured in $ms^{-1}$

t is time measured in seconds.

8 0

2 years ago

World class swimmers can swim the 100 meter in about 55 seconds what is their approximate average speed

Mice21 [21]

About 1.8181 meters per second

3 0

3 years ago

Read 2 more answers

Why should you use an iron hammer instead of a wooden <br> hammer?<br>

riadik2000 [5.3K]

Answer:

more durability and easier to pound a hammer with the heavy weight.

Explanation:

5 0

2 years ago

A length of copper wire carries a current of 11 A, uniformly distributed through its cross section. Calculate the energy density

NISA [10]

Answer:

a) $0.983 \frac{J}{m^3}$

b) $u_E =7.329x10^-3 \frac{J}{m^3}$

Explanation:

The energy density is "the energy per unit volume, in the electric field. The energy stored between the plates of the capacitor equals the energy per unit volume stored in the electric field times the volume between the plates".

A magnetic field is a "vector field that describes the magnetic influence of electric charges in relative motion and magnetized materials".

Part a

For this case we can assume use the equation for the magnetic field in terms of the energy per unit of volume.

$B=\sqrt{2\mu_o u}$

Where μ0 represent the permeability constant, also known as the magnetic constant. If we solve for u we got:

$u=\frac{B^2}{2\mu_o}$

We also know that the magnetic field can be expressed in terms of the current and the radius of action R like this:

$B=\frac{\mu_o i}{2\pi R}$

Replacing this on the formula for u we have:

$u=\frac{1}{2\mu_o}(\frac{\mu_o i}{2\pi R})^2$

And simplyfing we got:

$u=\frac{\mu_o i^2}{8\pi^2 R^2}$

Replacing the values given we have:

$u=\frac{(4\pix10^{-7} \frac{H}{m} (11A)^2}{8\pi^2 (0.0014m)^2} =0.983 \frac{J}{m^3}$

Part b

The density current is given by this formula $J=i/A$ and the resistance by $R=\frac{\rho l}{A}$

If we use the equation for the energy density we have this:

$u_E =\frac{1}{2}\varepsilon_o E^2 =\frac{\varepsilon}{2}(\rho J)^2=\frac{\varepsilon}{2}(\frac{iR}{l})^2$

And replacing the values given we have:

$u_E =\frac{8.85x10^{-12}\frac{F}{m}}{2}(\frac{11A(3700\frac{\Omega}{m})}{l})^2 =7.329x10^-3 \frac{J}{m^3}$

4 0

3 years ago

Which comparison is correct?

AleksandrR [38]

Considering their pKa, we can affirm that PH₃ is a stronger acid than NH₃.

We want to compare the strength of different acids. To do so, we need to compare their pKa.

The pKa is the negative base 10 logarithm of the acid dissociation constant, Ka.

The lower the pKa, the stronger the acid.

Which comparison is correct?

HF is a stronger acid than HCI. FALSE. The pKa of HF is 3.1. and the pKa of HCl is 6.0.
H₂S is a stronger acid than HCI. FALSE. The pKa₁ of H₂S is 7.04. and the pKa of HCl is 6.0.
PH₃ is a stronger acid than NH₃. TRUE. The pKa of PH₃ is -5.5 and the pKa of NH₃ is 9.9.
NH₃ is a stronger acid than HF. FALSE. The pKa of NH₃ is 9.9 and the pKa of HF is 3.1.

Considering their pKa, we can affirm that PH₃ is a stronger acid than NH₃.

Learn more about pKa here: brainly.com/question/13608171

4 0

2 years ago

What is the heaviest planet in the worlx​

What is the heaviest planet in the worlx