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
Andrej [43]
3 years ago
13

Two skiers arrive at the bottom of a ramp travelling at the same speed. Friction may be ignored in this problem. One skier is an

adult and one is a child. The adult has 3 times the mass of the child. Which skier makes it to a greater height on the ramp before coming to a stop?
Physics
1 answer:
inysia [295]3 years ago
6 0

Answer:

Both will reach to same height

Explanation:

Here we can see that friction is to be ignored

so we can say that work done by all the non conservative forces is change in mechanical energy

Since all non conservative forces here is zero

so mechanical energy is conserved here

so here we can say that sum of initial kinetic energy and potential energy = sum of final kinetic energy and potential energy

So we will have

\frac{1}{2}mv^2 = mgH

now maximum height is given as

H = \frac{v^2}{2g}

so here we can say that greatest height will be independent of the mass so they both will reach at same height

You might be interested in
Do electric fields point towards or away from positive charges?
juin [17]

Answer:

it points towards positive charges

3 0
3 years ago
A sphere of radius r = 5cm carries a uniform volume charge density rho = 400 nC/m^3. Q. What is the total charge Q of the sphere
Tanzania [10]

Answer:

The total charge Q of the sphere is 2.094\times10^{-10}\ C.

Explanation:

Given that,

Radius = 5 cm

Charge density J= 400\ nC/m^3

We need to calculate the total charge Q of the sphere

Using formula of charge

q=\rho V

Where, \rho = charge density

V = volume

Put the value into the formula

q=\rho\times(\dfrac{4}{3}\pi r^3)

Put the value into the formula

q=\dfrac{4}{3}\times\pi\times400\times10^{-9}\times(5\times10^{-2})^3

q=2.094\times10^{-10}\ C

Hence, The total charge Q of the sphere is 2.094\times10^{-10}\ C.

6 0
3 years ago
Is it possible to have a charge of 5 x 10-20 C? Why?
ruslelena [56]

1) No

2) Yes

3) No

4) Equal and opposite

5) 32400 N

6) Repulsive

7) The electric force is 2.3\cdot 10^{39} times bigger than the gravitational force

Explanation:

1)

In nature, the minimum possible charge that an object can have is the charge of the electron, which is called fundamental charge:

e=1.6\cdot 10^{-19}C

Electrons are indivisible particles (they cannot be separated), this means that an object can have at least the charge equal to the charge of one electron (in fact, it cannot have a charge less than e, because it would meant that the object has a "fractional number" of electrons).

In this problem, the object has a charge of

Q=5\cdot 10^{-20}C

If we compare this value to e, we notice that Q, so no object can have a charge of Q.

2)

As we said in part 1), an object should have an integer number of electrons in order to be charged.

This means that the charge of an object must be an integer multiple of the fundamental charge, so we can write it as:

Q=ne

where

Q is the charge of the object

n is an integer multiple

e is the fundamental charge

Here we have

Q=2.4\cdot 10^{-18}C

Substituting the value of e, we find n:

n=\frac{Q}{e}=\frac{2.4\cdot 10^{-18}}{1.6\cdot 10^{-19}}=15

n is integer, so this value of the charge is possible.

3)

We now do the same procedure for the new object in this part, which has a charge of

Q=2.0\cdot 10^{-19}C

Again, the charge on this object can be written as

Q=ne

where

n is the number of electrons in the object

Using the value of the fundamental charge,

e=1.6\cdot 10^{-19}C

We find:

n=\frac{Q}{e}=\frac{2.0\cdot 10^{-19}}{1.6\cdot 10^{-19}}=1.25

n is not integer, so this value of charge is not possible, since an object cannot have a fractional number of electrons.

4)

To solve this part, we use Newton's third law of motion, which states that:

"When an object A exerts a force on an object B (Action force), then object B exerts an equal and opposite force on object A (reaction force)".

In this problem, we have two objects:

- A charge Q

- A charge 5Q

Charge Q exerts an electric force on charge 5Q, and we can call this action force. At the same time, charge 5Q exerts an electric force on charge Q (reaction force), and according to Newton's 3rd law, the two forces are equal and opposite.

5)

The magnitude of the electric force between two single-point charges is

F=k\frac{q_1 q_2}{r^2}

where

k is the Coulomb's constant

q1, q2 are the two charges

r is the separation between the two charges

In this problem we have:

q_1=+4.5\cdot 10^{-6}C is charge 1

q_2=+7.2\cdot 10^{-6}C is charge 2

r = 0.30 cm = 0.003 m is the separation

So, the electric force  between the two charges is

F=(9\cdot 10^9)\frac{(4.5\cdot 10^{-6})(7.2\cdot 10^{-6})}{(0.003)^2}=32400 N

6)

The electric force between two charged objects has direction as follows:

- If the two objects have charges of opposite signs (+ and -), the force between them is attractive

- If the two objects have charges of same sign (++ or --), the force between them is repulsive

In this problem, the two charges are:

q_1=+4.5\cdot 10^{-6}C is charge 1

q_2=+7.2\cdot 10^{-6}C is charge 2

We see that the two charges have same sign: therefore, the force between them is repulsive.

7)

The electric force between the proton and the electron in the atom can be written as

F_E=k\frac{q_1 q_2}{r^2}

where

q_1 = q_2 = e = 1.6\cdot 10^{-19}C is the magnitude of the charge of the proton and of the electron

r=5.3\cdot 10^{-11} m is the separation between them

So the force can be rewritten as

F_E=\frac{ke^2}{r^2}

The gravitational force between the proton and the electron can be written as

F_G=G\frac{m_p m_e}{r^2}

where

G is the gravitational constant

m_p = 1.67\cdot 10^{-27}kg is the proton mass

m_e=9.11\cdot 10^{-27}kg is the electron mass

Comparing the 2 forces,

\frac{F_E}{F_G}=\frac{ke^2}{Gm_p m_e}=\frac{(9\cdot 10^9)(1.6\cdot 10^{-19})^2}{(6.67\cdot 10^{-11})(1.67\cdot 10^{-27})(9.11\cdot 10^{-31})}=2.3\cdot 10^{39}

8 0
3 years ago
What happens when you want to move the boat forward? You pull the oars toward yourself.Explain why you do this.
vampirchik [111]

Answer:

You pull on the oars. By the third law, the oars push back on your hands, but that’s irrelevant to the motion of the boat. The other end of each oar (the blade) pushes against the water. By the third law, the water pushes back on the oars, pushing the boat forward.

8 0
3 years ago
Read 2 more answers
Which units are used to express kinetic energy?
labwork [276]

Answer:

The SI units for energy is Joules.

4 0
4 years ago
Read 2 more answers
Other questions:
  • A straight line can represent a _____-dimensional coordinate system.
    14·1 answer
  • Some hydrogen gas is enclosed within a chamber being held at 200^\ { C} with a volume of 0.025 \rm m^3. The chamber is fitted wi
    8·1 answer
  • Emma is working in a shoe test lab measuring the coefficient of friction for tennis shoes on a variety of surfaces. The shoes ar
    10·1 answer
  • Phosphorus is most abundant in the: a)lithosphere b)atmosphere c)hydrosphere d)cryosphere
    5·2 answers
  • To keep the calculations fairly simple, but still reasonable, we shall model a human leg that is 92.0 cm long (measured from the
    9·1 answer
  • What are some applications of Kepler’s laws still in use today?
    14·2 answers
  • Why is it hard to breathe when you go higher up
    7·1 answer
  • Dolphins rely on echolocation to be able to survive in the ocean. In a 20 °C ocean, a dolphin produces an ultrasonic sound with
    13·1 answer
  • 3.
    8·1 answer
  • Ms. Senko is moving a desk around her classroom, the desk weighs 125N.
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!