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
const2013 [10]
3 years ago
14

A 0.140-kg baseball is dropped from rest. It has a speed of 1.20 m/s just before it hits the ground, and it rebounds with an upw

ard speed of 1.00 m/s. The ball is in contact with the ground for 0.0140 s.
Required:
What is the average force exerted by the ground on the ball during this time? Also explain whether it's upwards or downwards.
Physics
1 answer:
irga5000 [103]3 years ago
6 0

Answer:

22 N upward

Explanation:

From the question,

Applying newton's second law of motion

F = m(v-u)/t....................... Equation 1

Where F = Average force exerted by the ground on the ball, m = mass of the baseball, v = final velocity, u = initial velocity, t = time of contact

Note: Let upward be negative and downward be positive

Given: m = 0.14 kg, v = -1.00 m/s, u = 1.2 m/s, t = 0.014 s

Substitute into equation 1

F = 0.14(-1-1.2)/0.014

F = 0.14(-2.2)/0.014

F = 10(-2.2)

F = -22 N

Note the negative sign shows that the force act upward

You might be interested in
Which of these is an example of a mechanical wave
anastassius [24]
Some of the most common examples of mechanical waves are water waves, sound waves, and seismic waves. There are three types of mechanical waves: transverse waves, longitudinal waves, and surface waves.
6 0
3 years ago
Which equation relates charge, time, and current?
Ierofanga [76]

Answer:

I = Δq / t

Explanation:

The quantity of electricity i.e charge is related to current and time according to the equation equation:

Q = It

Δq = It

Where:

Q => is the quantity of electricity i.e charge

I => is the current.

t => is the time.

Thus, we can rearrange the above expression to make 'I' the subject. This is illustrated below:

Δq = It

Divide both side by t

I = Δq / t

6 0
2 years ago
the ratio of the energy per second radiated by the filament of a lamp at 250k to that radiated at 2000k, assuming the filament i
Naily [24]

Answer:

(a) \frac{P_{250k}}{P_{2000k}}=2.4\ x\ 10^{-4}

(b) P =  0.816 Watt

Explanation:

(a)

The power radiated from a black body is given by Stefan Boltzman Law:

P = \sigma AT^4

where,

P = Energy Radiated per Second = ?

σ = stefan boltzman constant = 5.67 x 10⁻⁸ W/m².K⁴

T = Absolute Temperature

So the ratio of power at 250 K to the power at 2000 K is given as:

\frac{P_{250k}}{P_{2000k}}=\frac{\sigma A(250)^4}{\sigma A(2000)^4}\\\\\frac{P_{250k}}{P_{2000k}}=2.4\ x\ 10^{-4}

(b)

Now, for 90% radiator blackbody at 2000 K:

P = (0.9)(5.67\ x\ 10^{-8}\ W/m^2.K^4)(1\ x\ 10^{-6}\ m^2)(2000\ K)^4

<u>P =  0.816 Watt</u>

7 0
3 years ago
According to Bernoulli's equation, the pressure in a fluid will tend to decrease if its velocity increases. Assuming that a wind
Pie

Answer:

The pressure drop predicted by Bernoulli's equation for a wind speed of 5 m/s

= 16.125 Pa

Explanation:

The Bernoulli's equation is essentially a law of conservation of energy.

It describes the change in pressure in relation to the changes in kinetic (velocity changes) and potential (elevation changes) energies.

For this question, we assume that the elevation changes are negligible; so, the Bernoulli's equation is reduced to a pressure change term and a change in kinetic energy term.

We also assume that the initial velocity of wind is 0 m/s.

This calculation is presented in the attached images to this solution.

Using the initial conditions of 0.645 Pa pressure drop and a wind speed of 1 m/s, we first calculate the density of our fluid; air.

The density is obtained to be 1.29 kg/m³.

Then, the second part of the question requires us to calculate the pressure drop for a wind speed of 5 m/s.

We then use the same formula, plugging in all the parameters, to calculate the pressure drop to be 16.125 Pa.

Hope this Helps!!!

7 0
3 years ago
Which two formulas are used to calculate potential and kinetic energy
goblinko [34]

Answer:

gravitational potential energy:

GPE = m g h

kinetic energy:

KE = 1/2 m v^2

6 0
3 years ago
Read 2 more answers
Other questions:
  • Question 17 options:A 71.8 kg man goes from an area where the acceleration due to gravity is 9.79 m/s2 to an area where the acce
    8·1 answer
  • Which involves reflection of light waves? A. A full moon shows sunlight bouncing off the moon's surface and traveling toward Ear
    8·2 answers
  • Why have fossil fuels become our primary energy resource
    12·2 answers
  • What is the concentration of OH– ions at a pH = 6?
    5·1 answer
  • Two cars A and B, travel in a straight line. The distance of A from the starting point is given as a function of time by x????(?
    14·2 answers
  • What is population education?<br>​
    14·2 answers
  • Identify conditions that can contribute to an increase in wind erosion.
    9·2 answers
  • Which weighs more a pound of feathers or a pound of bricks
    7·1 answer
  • What is movement energy?
    12·2 answers
  • b. Describe in general how terminator devices capture the power of waves. In particular, explain how the oscillating water colum
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!