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
melomori [17]
3 years ago
7

An object is dropped near the earth's surface. At the end of 4.0 s, how fast is it falling in m/s? (Ignore air resistance.)

Physics
2 answers:
Sati [7]3 years ago
7 0
For free falling bodies, the final velocity may be calculated through the equation,
                                   Vf = gt
Where g is the acceleration due to gravity (9.8 m/s²) and t is the time elapsed. Substituting the known values,
                                   Vf = (9.8 m/s²) x (4 s) = 39.2 m/s
Therefore, the object's velocity is approximately 39.2 m/s. 
DochEvi [55]3 years ago
4 0

The answer would be 39.2 m/s

You might be interested in
Which of the following is a vector quantity?
djverab [1.8K]

Vector quantity is defined by direction as well as magnitude both

so now lets discuss all option

1) distance = it is total path length between two points so there is no direction needed in it so it is scalar

2) Speed = it is ratio of total distance covered and total time, so it also do not require any direction.

<em>3)velocity = it is ratio of displacement and time, and displacement is always given with direction so velocity is a vector quantity</em>

4) time = time is the measurement of the interval of two events and we do not require any direction in it so its a scalar quantity.

4 0
2 years ago
A motorist, traveling east on an open highway, sets his cruise control at 90.0 km/h. How far will he travel in 0.75 hours?
dimaraw [331]

Answer:

<h2>The answer is 67.5 km</h2>

Explanation:

The distance covered by an object given it's velocity and time taken can be found by using the formula

distance = velocity × time

From the question we have

distance = 90 × 0.75

We have the final answer as

<h3>67.5 km</h3>

Hope this helps you

3 0
2 years ago
Read 2 more answers
12 POINTS PLEASE HELP.
bazaltina [42]
<span>Are programs that basically want to publicize the lives of other people sopadamente to help them</span>
3 0
3 years ago
A battery with an emf of 12.0 V shows a terminal voltage of 11.7 V when operating in a circuit with two lightbulbs, each rated a
wariber [46]
<h2>Answer:</h2>

0.46Ω

<h2>Explanation:</h2>

The electromotive force (E) in the circuit is related to the terminal voltage(V), of the circuit and the internal resistance (r) of the battery as follows;

E = V + Ir                      --------------------(a)

Where;

I = current flowing through the circuit

But;

V = I x Rₓ                    ---------------------(b)

Where;

Rₓ = effective or total resistance in the circuit.

<em>First, let's calculate the effective resistance in the circuit:</em>

The effective resistance (Rₓ) in the circuit is the one due to the resistances in the two lightbulbs.

Let;

R₁ = resistance in the first bulb

R₂ = resistance in the second bulb

Since the two bulbs are both rated at 4.0W ( at 12.0V), their resistance values (R₁ and R₂) are the same and will be given by the power formula;

P = \frac{V^{2} }{R}

=> R = \frac{V^{2} }{P}             -------------------(ii)

Where;

P = Power of the bulb

V = voltage across the bulb

R = resistance of the bulb

To get R₁, equation (ii) can be written as;

R₁ = \frac{V^{2} }{P}    --------------------------------(iii)

Where;

V = 12.0V

P = 4.0W

Substitute these values into equation (iii) as follows;

R₁ = \frac{12.0^{2} }{4}

R₁ = \frac{144}{4}

R₁ = 36Ω

Following the same approach, to get R₂, equation (ii) can be written as;

R₂ = \frac{V^{2} }{P}    --------------------------------(iv)

Where;

V = 12.0V

P = 4.0W

Substitute these values into equation (iv) as follows;

R₂ = \frac{12.0^{2} }{4}

R₂ = \frac{144}{4}

R₂ = 36Ω

Now, since the bulbs are connected in parallel, the effective resistance (Rₓ) is given by;

\frac{1}{R_{X} } = \frac{1}{R_1} + \frac{1}{R_2}       -----------------(v)

Substitute the values of R₁ and R₂ into equation (v) as follows;

\frac{1}{R_X} = \frac{1}{36} + \frac{1}{36}

\frac{1}{R_X} = \frac{2}{36}

Rₓ = \frac{36}{2}

Rₓ = 18Ω

The effective resistance (Rₓ) is therefore, 18Ω

<em>Now calculate the current I, flowing in the circuit:</em>

Substitute the values of V = 11.7V and Rₓ = 18Ω into equation (b) as follows;

11.7 = I x 18

I = \frac{11.7}{18}

I = 0.65A

<em>Now calculate the battery's internal resistance:</em>

Substitute the values of E = 12.0, V = 11.7V and I = 0.65A  into equation (a) as follows;

12.0 = 11.7 + 0.65r

0.65r = 12.0 - 11.7

0.65r = 0.3

r = \frac{0.3}{0.65}

r = 0.46Ω

Therefore, the internal resistance of the battery is 0.46Ω

5 0
3 years ago
Read 2 more answers
A 1-kilogram ball has a kinetic energy of 50 joules the speed of the ball is
sveta [45]

Answer:

10 m/s

Explanation:

3 0
2 years ago
Other questions:
  • Which statement is true for light passing into a medium that is more optically dense than the first medium through which it past
    14·1 answer
  • Eratosthenes determined the circumference of Earth by conducting an experiment. Put his steps in order as they correlate to the
    9·1 answer
  • A city’s bus line is used more as the urban population density increases. The more people in an area, the more likely bus lines
    15·2 answers
  • Ball A is dropped from the top of a building of height h at the same instant that ball B is thrown vertically upward from the gr
    7·1 answer
  • What is the difference between a do universal law and a scientific theory
    14·1 answer
  • With a magnetic field strength of 1.41 tesla, all of the protons in organic compounds will resonate over a narrow range of frequ
    11·1 answer
  • Why does a small pebble sin in water?
    7·1 answer
  • CAN SOMEONE PLEASE HELP ME ASAP PLEASE !!!!!​
    15·1 answer
  • What tension must a 50.0 cm length of string support in order to whirl an attached 1,000.0 g stone in a circular path at 5.00 m/
    8·1 answer
  • Hai xe chuyển động trên cùng một đoạn đường , khi xe (1) ở A thì xe (2) ở B phía trước với AB=5km . Xe (1) đuổi theo xe (2) . Tạ
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!