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
Mumz [18]
3 years ago
14

A rock is thrown horizontally off a cliff with an initial speed of 3 m/s. The initial position of the rock is 10 meters above th

e ground. How long is the rock in the air?
Physics
1 answer:
Valentin [98]3 years ago
3 0

Answer:

<em>1.43 s.</em>

Explanation:

Using one of the equations of motion,

S = ut + 1/2gt².......................... Equation 1

Where S = height of the cliff, u = initial velocity, t = time, g = acceleration due to gravity.

<em>Note: When the rock begins to fall from the maximum height, u = 0 m/s, g = positive</em>

<em>Given: S = 10 m, u = 0 m/s</em>

<em>Constant: g = 9.8 m/s²</em>

<em>Substituting these values into equation,</em>

<em>10 = 0(t) + 1/2(9.8)(t²)</em>

<em>10 = 0 + 4.9t²</em>

<em>t² = 10/4.9</em>

<em>t² = 100/49</em>

<em>t = √(100/49)</em>

<em>t = 10/7</em>

<em>t = 1.43 s.</em>

<em>Thus the rock spend 1.43 s in air</em>

You might be interested in
Concave lens cause rays to _____.
Molodets [167]
Diverge or spread apart.
5 0
3 years ago
On the graph of voltage versus current, which line represents a 2.0 Ω resistor?​
Vikki [24]

Answer:

<h2>line B</h2>

Explanation:

According to ohm's law V = IR where;

V i sthe supply voltage (in volts)

I = supply current (in amperes)

R = resistance (in ohms)

In order to calculate the line that is equal to 2ohms, we need to calculate the slope of each line using the formula.

For line B, R = ΔV/ΔI

R = V₂-V₁/I₂-I₁

R = 14.0-4.0/7.0-2.0

R = 10.0/5.0

R = 2.0ohms

Since the slope of line B is equal to 2 ohms, this shows that the line B is the one that represents the 2ohms resistor.

3 0
4 years ago
Suppose the magnitude of the proton charge differs from the magnitude of the electron charge by a mere 1 part in 109
Oksana_A [137]

Answer:

 A) F = 1.09 10 5 N, b) Yes  

Explanation:

Part A

For this exercise we need the number of free electrons in copper, as the valence of copper +1 there is a free electron for each atom. Let's use the concept of density to find the mass of copper in the sphere

               ρ = m / V

               .m = ρ V = ρ 4/3 π r³

The radius is half the diameter

               r = 1.9 10⁻² / 2 = 0.95 10⁻² m

               ρ = 8960 kg / m3

               m = 8960 4/3 π (0.95 10⁻²)³

               m = 3.2179 10⁻² kg

The molecular weight of copper is 63,546 g / mol which has 6,022 10²³ atoms

With this we can use a rule of proportions to enter the number of atom is this mass

             #_atom = 6.022 10²³ 3.2179 10⁻² / 63.546 10⁻³

             #_atom = 3,049 10²³

Therefore there is the same number of electrons, as they indicate that the charge of the protone and the electon differs by 1/10⁹ the total charge for each spherical is

               q = e / 10⁹    #_atom

               q = e / 10⁹    3,049 1023

               q = 3,049 10⁴  (-1.6 10⁻¹⁹)

               q = -4,878 10-5 C

Electric force is

             F = k q₁q₂ / r²

             F = k q² / r²

             

Let's calculate

             F = 8.99 10⁹ (4.878 10⁻⁵)²2 / (1.4 10⁻²)²

              F = 1.09 10 5 N

This is a force of repulsion.

Part B

 The magnitude of this force is  in very easy to detect

4 0
3 years ago
you push a sled of mass 15 kg across the snow with a force of 180 N for a distance of 2.5 m. There is no friction. if the sled s
Oxana [17]
<span>7.7 m/s First, determine the acceleration you subject the sled to. You have a mass of 15 kg being subjected to a force of 180 N, so 180 N / 15 kg = 180 (kg m)/s^2 / 15 kg = 12 m/s^2 Now determine how long you pushed it. For constant acceleration the equation is d = 0.5 A T^2 Substitute the known values getting, 2.5 m = 0.5 12 m/s^2 T^2 2.5 m = 6 m/s^2 T^2 Solve for T 2.5 m = 6 m/s^2 T^2 0.41667 s^2 = T^2 0.645497224 s = T Now to get the velocity, multiply the time by the acceleration, giving 0.645497224 s * 12 m/s^2 = 7.745966692 m/s After rounding to 2 significant figures, you get 7.7 m/s</span>
5 0
4 years ago
250 mL 0.1 M HCl solution is mixed with 250 mL
pishuonlain [190]

Answer:

The concentration of OH⁻ in the mixture is 0.05 M

Explanation:

The reaction of neutralization between HCl and NaOH is the following:

H⁺(aq) + OH⁻(aq) ⇄  H₂O(l)

The number of moles of HCl is:

n_{HCl} = C*V = 0.1 mol/L*0.250L = 0.025 moles

Similarly, the number of moles of NaOH is:

n_{NaOH} = C*V = 0.2 mol/L*0.250L = 0.05 moles

Now, from the reaction of HCl and NaOH we have the following number of moles of NaOH remaining:

n_{NaOH} = 0.05 moles - 0.025 moles = 0.025 moles

Finally, the concentration of OH⁻ in the mixture is:

C =\frac{n_{NaOH}}{V_{T}}=\frac{0.025 moles}{0.250*2 L} = 0.05 moles/L

Therefore, the concentration of OH⁻ in the mixture is 0.05 M.

I hope it helps you!

8 0
3 years ago
Other questions:
  • Name the missing force... Normal <br>   Spring <br>   Tension <br>   Air Resistance
    8·1 answer
  • What is the most common consumed Halloween candy in the us after chocolate
    14·1 answer
  • When a theory is disproved by further evidence, which of the following occurs?
    10·2 answers
  • The point beneath surface where rock breaks and an arthquake is produced is known as the
    15·1 answer
  • In addition to gravity, what is the other predominant force that affects the motion of a pendulum?
    7·1 answer
  • Arrange the following substances in order of decreasing magnitude of lattice energy. Rank the compounds in order of decreasing m
    13·2 answers
  • A train is travelling at 15m/s. It accelerates at 3m/s² for 20 seconds. How far does the train travel in this time?
    11·1 answer
  • The front end of the car is crushing and absorbing ___ which slows down the rest of the car
    9·1 answer
  • A 10 kg box initially at rest is pulled with a 50 N horizontal force for 4 m across a level surface. The force of friction actin
    14·1 answer
  • how does the kinetic energy of particles relate to the temperature of the substance containing those particles, also show the eq
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!