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
Paladinen [302]
3 years ago
14

. A child drops a ball from a window. The ball strikes the ground in 3.0 seconds. What is the. A child drops a ball from a windo

w. The ball strikes the ground in 3.0 seconds. What is the
velocity of the ball the instant before it hits the ground?
Physics
1 answer:
Vsevolod [243]3 years ago
3 0

Answer:

30m/s

Explanation:

  • Use formula for height calculation: Time = √2h/√g
  • From here calculate height which comes out to be: 45m(if g is taken 10)
  • Then use formula for velocity calculation: v = √2gh

  • The velocity comes out to be 30m/s

You might be interested in
Which describes sublimation?
balu736 [363]
A. Solid turns into a gas
5 0
3 years ago
A proposed communication satellite would revolve around the earth in a circular orbit in the equatorial plane at a height of 358
aleksandr82 [10.1K]

Answer:

Period is 86811.5 seconds.

Explanation:

{ \boxed{ \bf{T {}^{2} =  (\frac{4 {\pi}^{2} }{GM}) {r}^{3}   }}}

{ \tt{T {}^{2}  =  \frac{4 {(3.14)}^{2} }{(6.6 \times  {10}^{ - 11} ) \times (5.98 \times  {10}^{24} )} \times  {((35880\times  {10}^{3}) } + (6370 \times  {10}^{3} )) {}^{3}   }} \\  \\ { \tt{T {}^{2}  =  7.54 \times {10}^{9} }} \\ { \tt{T =  \sqrt{7.54 \times  {10}^{9} } }} \\ { \tt{T = 86811.5 \: seconds}}

6 0
3 years ago
Which of the following are inertial reference frames? A. A car driving at steady speed on a straight and level road. B. A car dr
Aloiza [94]

Answers:

A. A car driving at steady speed on a straight and level road.

B. A car driving at steady speed up a 10∘ incline.

Explanation:

An object is said to be in an inertial reference frame if the net force acting on the object is zero. According to Newton's second law, this also means that the acceleration of the object is also zero:

F=ma

Since F=0, a=0 as well.

Let's now analyze each case.

A. A car driving at steady speed on a straight and level road. --> YES: this is an inertial reference frame, because the car is keeping a constant speed and a constant direction, so its velocity is not changing, and its acceleration is zero.

B. A car driving at steady speed up a 10∘ incline. --> YES: this is an inertial reference frame, because the car is keeping a constant speed and a constant direction, so its velocity is not changing, and its acceleration is zero.

C. A car speeding up after leaving a stop sign. --> NO: this is not an intertial reference frame, because the car is speeding up, so it is accelerating.

D. A car driving at steady speed around a curve. --> NO: this is not an inertial reference frame, because the car is changing direction, therefore its velocity is changing and so the car is accelerating.

So the only two choices which are correct are A and B.

8 0
3 years ago
Read 2 more answers
Which is not a common property of ionic compounds?
Dmitriy789 [7]

Answer:

low melting point

Ionic compounds have high melting and boiling points. This is because a considerable amount of energy is required to break the strong inter-ionic attraction

Explanation:

8 0
3 years ago
The mass of an object changes as the distance from the center of gravity changes.
Alchen [17]

Answer:

true

Explanation:

this is the answer to this question

8 0
3 years ago
Other questions:
  • Newton's First Law of Motion states that an object will remain at rest or in uniform motion in a straight line unless acted upon
    14·2 answers
  • 1. When an object's distance from another object is changing it must be
    12·1 answer
  • What are the 2 ways to describe matter
    6·2 answers
  • Why wheat flour is usually passed near a magnet before being packed?
    10·1 answer
  • A circular loop of wire has radius of 9.50 cmcm. A sinusoidal electromagnetic plane wave traveling in air passes through the loo
    5·1 answer
  • A force of 20 N is executed to raise a rock weighing 30 N. What is the actual mechanical advantage?
    11·2 answers
  • What part of the diagram is labeled by the number 3?
    7·1 answer
  • In which application is a magnet used to store information?
    6·2 answers
  • 0.55 kg mouse moving E at 60m s or a 900 kg elephant moving E at 0.03m Which has the most momentum?
    14·1 answer
  • A body falls from rest under gravity, the velocity “v” is given by v=kgp h q , where h is the distance fallen through, g the acc
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!