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
Dafna1 [17]
3 years ago
6

If a ball with an original velocity of zero is dropped from a tall structure and it takes 7 seconds to hit the ground, what velo

city does the ball have when it reaches the ground? A. 34.3 m/s B. 68.6 m/s C. 156.8 m/s D. 240.1 m/s
Physics
2 answers:
Colt1911 [192]3 years ago
5 0
The velocity of the ball when it reaches the ground is equal to B. 68.6 m/s. This value was obtained from the formula Vf = Vi + at. Vf is the final velocity. Vi is the initial velocity. The acceleration is "a", while the time of travel is "t". The solution is:

<span>Vf = Vi + at
</span>Vf = 0 + (-9.8 m/s^2) (7 s)
Vf = -68.6 m/s

The negative sign denotes the direction of the ball.
Tatiana [17]3 years ago
5 0

If a ball with an original velocity of zero is dropped from a tall structure and takes 7 seconds to hit the ground, what velocity does the ball have when it reaches the ground?

A. 68.6 m/s

B. 34.3 m/s

C. 240.1 m/s

D. 156.8 m/s

You might be interested in
A certain frictionless simple pendulum having a length l and mass m swings with period t. If both l and m are doubled, what is t
iVinArrow [24]

If l and m both are doubled then the period becomes √2*T

what is a simple pendulum?

It is the one which can be considered to be a point mass suspended from a string or rod of negligible mass.

A pendulum is a weight suspended from a pivot so that it can swing freely.

Here,

A certain frictionless simple pendulum having a length l and mass m

mass of pendulum = m

length of the pendulum = l

The period of simple pendulum is:

T = 2\pi \sqrt{\frac{l}{g} }

Where k is the constant.

Now the length and mass are doubled,

m' = 2m

l' = 2l

T' = 2\pi \sqrt{\frac{2l}{g} }

T' = \sqrt{2}* 2\pi \sqrt{\frac{l}{g} }

T' = \sqrt{2} * T

Hence,

If l and m both are doubled then the period becomes √2*T

Learn more about Simple Harmonic Motion here:

<u>brainly.com/question/17315536</u>

#SPJ4

8 0
1 year ago
Students perform an experiment in which they drop two eggs with equal mass from a balcony. In the first trial, the egg hits the
shepuryov [24]

<u> Answer </u>

The impulse on the second trial is smaller is smaller than in the first trial.

<u>Explanation </u>

Impose of a body is that change in momentum during a time interval. If the change of momentum takes longer then, the impulse of a force is less. I a moving object hits a hard surface the rate of change of momentum is very high. e.i in the first trial, the egg breaks because it hits the hard surface(ground).

In the second trial, the foam cushion absorbs the shock and prolongs the time of impact with the egg hence decreasing the impulse.


8 0
3 years ago
Read 2 more answers
When a sinusoidal wave with speed 20 m/s , wavelength 35 cm and amplitude of 1.0 cm passes, what is the maximum speed of a point
vova2212 [387]

To solve this problem it is necessary to apply the concepts related to frequency as a function of speed and wavelength as well as the kinematic equations of simple harmonic motion

From the definition we know that the frequency can be expressed as

f = \frac{v}{\lambda}

Where,

v = Velocity \rightarrow 20m/s

\lambda = Wavelength \rightarrow 35*10^{-2}m

Therefore the frequency would be given as

f = \frac{20}{35*10^{-2}}

f = 57.14Hz

The frequency is directly proportional to the angular velocity therefore

\omega = 2\pi f

\omega = 2\pi *57.14

\omega = 359.03rad/s

Now the maximum speed from the simple harmonic movement is given by

V_{max} = A\omega

Where

A = Amplitude

Then replacing,

V_{max} = (1*10^{-2})(359.03)

V_{max} = 3.59m/s

Therefore the maximum speed of a point on the string is 3.59m/s

8 0
3 years ago
5. __________ is the idea that all people must follow the law and that the law is applied to all equally even people in the gove
padilas [110]
The answer is Rule of the law
5 0
3 years ago
In still​ water, a boat averages 18 18 miles per hour. it takes the same amount of time to travel 16 miles 16 miles ​downstream,
Vladimir79 [104]
<span>The current is 6 miles per hour.
   Let's create a few equations:
 Traveling with the current:
 (18 + c)*t = 16

   Traveling against the current:
 (18 - c)*t = 8

   Let's multiply the 2nd equation by 2
 (18 - c)*t*2 = 16

   Now subtract the 1st equation from the equation we just doubled.
 (18 - c)*t*2 = 16
 (18 + c)*t = 16

   (18 - c)*t*2 - (18 + c)*t = 0
 Divide both sides by t
 (18 - c)*2 - (18 + c) = 0

   Now solve for c
 (18 - c)*2 - (18 + c) = 0
 36 - 2c - 18 - c = 0
 36 - 2c - 18 - c = 0
 18 - 3c = 0
 18 = 3c
  6 = c

   So the current is 6 mph.
   Let's verify that.
 (18 + 6)*t = 16
 24*t = 16
 t = 16/24 = 2/3

   (18 - 6)*t = 8
 12*t = 8
 t = 8/12 = 2/3

   And it's verified.</span>
4 0
3 years ago
Other questions:
  • Why are bridges declared unsafe after a long use​
    14·1 answer
  • Which type of atom has the same number of protons and electrons
    14·1 answer
  • ASAP<br> describe how energy is transferred in a mechanical wave
    6·1 answer
  • Which factor indicates the amount of charge on the source charge?
    8·2 answers
  • What is the radius of a nucleus of an atom?
    13·2 answers
  • Which phenomenon occurs when light falls on a smooth mirror?
    5·1 answer
  • A metal disk of radius 6.0 cm is mounted on a frictionless axle. Current can flow through the axle out along the disk, to a slid
    12·1 answer
  • Where are protons, neutrons, and electrons in the atom?
    5·1 answer
  • A fiber-optic rod consists of a central strand of material surrounded by an outer coating. the interior portion of the rod has a
    7·1 answer
  • State that there are positive and negative charges.
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!