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
Tju [1.3M]
3 years ago
12

You are walking in Paris alongside the Eiffel Tower and suddenly a croissant falls on your head and knocks you to the ground. If

you neglect air resistance, calculate how many seconds the croissant dropped before it knocked you over if the velocity is 76.4 m/s.
Physics
2 answers:
Alexxandr [17]3 years ago
6 0

Answer:

7,79 seconds

Explanation:

{\displaystyle {\overline {a}}={\frac {\Delta v}{t}}}

You need to use the acceleration formula. A is acceliration, \displaystyle \Delta \mathbf {v} is change in velocity and t is time.

You  need to multiply the formula with t and divide by a and you get

a*t=\displaystyle \Delta \mathbf {v}

t= \displaystyle \Delta \mathbf {v}/a

after that you just need to insert the numbers

change in velocity is 76.4 minus 0.

acceliration is gravitational acceleration which is 9.81.

After that you get

t=76.4/9.81

t= 7,787971458 s

egoroff_w [7]3 years ago
6 0

Answer:

seconds of freefall and calculate the velocity at impact in mi/hr. I VE = 10.78 m/s ... You are walking in Paris alongside the Eiffel Tower and suddenly a croissant smacks you on the head and knocks you to the ground. From your handy ... If you neglect air resistance, calculate how many seconds the croissant dropped before it.

Explanation:

You might be interested in
Water is flowing through a 45° reducing pipe bend at a rate of 200 gpm and exits into the atmosphere (P2 = 0 psig). The inlet to
Nataliya [291]

Answer:

F1=177.88 Newtons

Explanation:

Let's start with the Bernoulli's equation:

P_{1} + \frac{1}{2}\beta V_{1} ^{2} + \beta gh_{1}  =P_{2} + \frac{1}{2}\beta V_{2} ^{2} + \beta gh_{2}

Where:

P is pressure, V is Velocity, g is gravity, h is height and β is density (for water β=1000 kg/m3); at the points 1 and 2 respectively.

From the Bernoulli's equation and assuming that h is constant and P2 is zero (from the data), we have:

P_{1} + \frac{1}{2}\beta V_{1} ^{2} = \frac{1}{2}\beta V_{2} ^{2}

As we know, P1 must be equal to \frac{F_{1} }{A_{1}}, so, replacing P1 in the equation, we have:

P_{1} = \frac{F_{1}}{A_{1}} = \frac{1}{2}\beta(V_{2} ^{2} - V_{1} ^{2})

And

F_{1} = {A_{1}} ( \frac{1}{2}\beta(V_{2} ^{2} - V_{1} ^{2}))

Now, let's find the velocity to replace the values on the expression:

We can express the flow in function of velocity and area as Q = V A, where Q is flow, V is velocity and A is area. As the same, we can write this: Q_{1} = V_{1} A_{1}\\Q_{2} = V_{2} A_{2}. In the last two equations, let's clear Velocities.

V_{1} = \frac{Q_{1}}{A_{1}}\\V_{2} = \frac{Q_{2}}{A_{2}}

and replacing V1 and V2 on the last equation resulting from Bernoulli's (the one that has the force on it):

F_{1} = {A_{1}} ( \frac{1}{2}\beta((\frac{Q_{2}}{A_{2}})^{2} - (\frac{Q_{1}}{A_{1}})^{2}))

First, we have to consider that from a mass balance, the flow is the same, so Q1=Q2, what changes, is the velocity. Knowing this, let's write the areas, diameters, density and flow on International Units System (S.I.), because the exercise is asking us the answer in Newtons.

D_{1}=1.5 inches=0.0381 mts\\D_{2}=1 inches=0.0254 mts\\A_{1}=\frac{\pi D_{1}^{2} }{4}=0.00114mts^{2}\\A_{2}=\frac{\pi D_{2}^{2} }{4}=0.000507mts^{2}\\\beta=1000 kgs/m^{3}\\Q=200gpm=0.01mts^{3}/seg

Replacing the respective values in this last expression, we obtain:

F1 = 177.88 N

3 0
3 years ago
A dielectric material is inserted between the charged plates of a parallel-plate capacitor. Do the following quantities increase
ch4aika [34]

Answer:

1. Charge on plates (plates remain connected to battery) increases.

2. Electric potential energy (plates isolated from battery before inserting dielectric) decreases.

3.Capacitance (plates isolated from battery before inserting dielectric) increases.

4. Voltage between plates (plates remain connected to battery) remains the same.

5. Charge on plates (plates isolated from battery before inserting dielectric) remains the same.

6. Capacitance (plates remain connected to battery) increases.

7. Electric potential energy (plates remain connected to battery) increases.

8. Voltage between plates (plates isolated from battery before inserting dielectric) decreases.

Explanation:

When a dielectric material is inserted between the plates of a capacitor, the capacitance is increase by a factor K, the dielectric constant.

C = KC_0

By the capacitance formula, the other factors change accordingly.

1. Charge on plates (plates remain connected to battery) increases, because charge and capacitance are directly proportional.

2. Electric potential energy (plates isolated from battery before inserting dielectric) decreases, because potential is inversely proportional to capacitance, and potential energy is given by the following formula

U = \frac{1}{2}CV^2

3.Capacitance (plates isolated from battery before inserting dielectric) increases.

4. Voltage between plates (plates remain connected to battery) stays the same, because the voltage is applied by the battery.

5. Charge on plates (plates isolated from battery before inserting dielectric) remains constant. If the plates isolated from the battery, then the total charge is conserved.

6. Capacitance (plates remain connected to battery)  increases when a dielectric is inserted.

7. Electric potential energy (plates remain connected to battery)  increases, because when plates remain connected to battery the voltage remains the same. But the capacitance increases. Therefore, electric potential energy increases.

8. Voltage between plates (plates isolated from battery before inserting dielectric) decreases, because voltage is inversely proportional to capacitance.

5 0
3 years ago
. A paper airplane of .025kg is falling at a rate 2m/s2. What is the amount of net force?
Pie

Answer:

<h2>0.05 N</h2>

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 0.025 × 2

We have the final answer as

<h3>0.05 N</h3>

Hope this helps you

6 0
2 years ago
Calculate the mass of -1.5C of electrons​
algol13
The electron is a type of low-mass, very negatively charged with a particle. As such, it can easily be deflected by passing close to other electrons or the positive nucleus of an atom. m = mass of an electron in kg = 9.10938356 × 10-31 kilograms. e = magnitude of the charge of an electron in coulombs = 1.602 x 10-19 coulombs. Hope this helps!
8 0
3 years ago
What is the average velocity of a car that travels 50 kilometers due west in 0.50 hour?
Pie

Average Velocity= displacement/time   Av=50/0.50   Av=100

4 0
3 years ago
Other questions:
  • compare 51.5 hectograms to 51500 decigrams. How do each of these values compare to a gram, and which represents a larger mass?
    11·1 answer
  • In a redox reaction, why does an element’s oxidation number decrease?
    11·2 answers
  • Determine how many Altuves you could travel in a day if you were moving at 45.000 mph all day. Altuve = 1.65 m
    5·1 answer
  • A gas is compressed from an initial volume of 5.65 L to a final volume of 1.24 L by an external pressure of 1.00 atm. During the
    15·1 answer
  • Define the unit of current​
    10·1 answer
  • Why do liquids and gases take the shape of their containers while solids do not ?
    14·2 answers
  • The velocity of an object moving along a straight line is given by – v(t) = t 2 − 3t + 2 (a) Find the displacement of the object
    10·1 answer
  • Consider a magnetic force acting on an electric charge in a uniform magnetic field. Which of the following statements are true?
    10·1 answer
  • Define Kinetic Energy:
    10·2 answers
  • 1) When you hold your nose and go underwater, you can still hear sounds that are made above the water, in the air, if they are l
    5·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!