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
butalik [34]
3 years ago
15

A projectile is launched straight up from a height of 960 feet with an initial velocity of 64 ft/sec. Its height at time t is h(

t)=−16t2+64t+960. Answer the following questions, including units in each answer. At what time does it reach its maximum height? Hint: Its velocity is zero at its maximum height. How high will it go? What is its velocity at the instant it reaches the ground?
Physics
1 answer:
Natasha2012 [34]3 years ago
5 0

Answer:

a) t=2s

b) h_{max}=1024ft

c) v_{y}=-256ft/s

Explanation:

From the exercise we know the initial velocity of the projectile and its initial height

v_{y}=64ft/s\\h_{o}=960ft\\g=-32ft/s^2

To find what time does it take to reach maximum height we need to find how high will it go

b) We can calculate its initial height using the following formula

Knowing that its velocity is zero at its maximum height

v_{y}^{2}=v_{o}^{2}+2g(y-y_{o})

0=(64ft/s)^2-2(32ft/s^2)(y-960ft)

y=\frac{-(64ft/s)^2-2(32ft/s^2)(960ft)}{-2(32ft/s^2)}=1024ft

So, the projectile goes 1024 ft high

a) From the equation of height we calculate how long does it take to reach maximum point

h=-16t^2+64t+960

1024=-16t^2+64t+960

0=-16t^2+64t-64

Solving the quadratic equation

t=\frac{-b±\sqrt{b^{2}-4ac}}{2a}

a=-16\\b=64\\c=-64

t=2s

So, the projectile reach maximum point at t=2s

c) We can calculate the final velocity by using the following formula:

v_{y}^{2}=v_{o}^{2}+2g(y-y_{o})

v_{y}=±\sqrt{(64ft/s)^{2}-2(32ft/s^2)(-960ft)}=±256ft/s

Since the projectile is going down the velocity at the instant it reaches the ground is:

v=-256ft/s

You might be interested in
Determine the Reynolds number for a flow of 0.2 m^3/s through a 203 mm inner diameter circular pipe of a fluid with rho=680 kg/m
IrinaK [193]

To find a solution to this problem it is necessary to apply the concepts related to the Reynolds number and its definitions on the type of fluid.

A Reynolds number less than 2000 considers the laminar fluid, while a Reynolds number greater than 4000 is considered a turbulent fluid. (The intermediate between the two values would be a transient fluid)

The mathematical equation that defines the Reynolds number is given by

Re = \frac{\rho V D}{\mu}

Where

\rho = Density

V= Velocity

D= Diameter

\mu = Viscosity

Our values are given as

Q = 0.2m^3/s

D = 203*10^{-3}m

\rho = 680kg/m^3

\mu = 3.1*10^{-4}Ns/m^2

\sigma = 0.022N/m

The velocity can be find through the Discharge equation,

Q = VA

Where

V = Velocity

A = Area

Replacing,

0.2 = V* (2\pi*(\frac{203*10^{-3}}{2})^2)

V = 3.08m/s

Replacing at the Reynolds equation,

Re = \frac{\rho VD}{\mu}

Re = \frac{680*3.08*203*10^{-3}}{3.1*10^{-4}}

Re = 1.37*10^6

Since Reynolds' number is greater than 4000, then we consider this a turbulent fluid.

3 0
3 years ago
The process in which acids and bases react so that the properties of both are lost to form water and a salt is called __________
makvit [3.9K]
The process is called neutralization.
Hope this helps!
4 0
3 years ago
How far will 350 j raise a 7 kg mass?
DaniilM [7]
W=350 J=M g H
Solve for the height, H
G=9.8 m/s^2
M=7kg
H will be in meters if you use those units.
6 0
3 years ago
A stone is dropped from a cliff and falls 9.44 meters. What is the speed of the stone when it reaches the ground?
Lunna [17]

Answer:

option A

Explanation:

given,                                              

height of the drop of stone = 9.44 m

speed of the stone = ?                          

As the stone is dropped the energy of the stone will be conserved.

using conservation of energy.            

Potential energy = Kinetic energy    

m g h = \dfrac{1}{2} m v^2  

     v = \sqrt{2gh}                  

     v = \sqrt{2\times 9.8 \times 9.44}

     v = \sqrt{185.024}              

            v = 13.60 m/s                      

Hence, the correct answer is option A

3 0
3 years ago
Correct Number Formats Numbers may be entered in several formats - including scientific notation and numerical expressions.
Illusion [34]

Answer:

a. Valid

b. Invalid

c. Invalid

d. Invalid

e. Valid

f.  Valid

g. Invalid

Explanation:

a.

Since, it follows all the four rules,

Therefore, this number is <u>Valid</u>

b.

It uses upper case E, instead of lower case e.

Therefore, it is <u>Invalid</u>

c.

It violates third rule for including unit.

Therefore, it is <u>Invalid</u>

d.

It violates the first rule. As, there is a space between 6 and e. While in the example given in question, there is no gap.

Therefore, it is <u>Invalid</u>

e.

Since, it follows all the four rules,

Therefore, this number is <u>Valid</u>

f.

Since, it follows all the four rules,

Therefore, this number is <u>Valid</u>

g.

It violates third rule for including unit.

Therefore, it is <u>Invalid</u>

6 0
3 years ago
Other questions:
  • If the two spheres are then connected by a conducting wire what will be the final charges on the spheres?
    5·1 answer
  • Which statement about a pair of units is true? A yard is shorter than a meter. Amile is shorter than a kilometer. A foot is shor
    12·1 answer
  • If the Doppler radar is measuring an echo of 41 dBZ, what is the corresponding rainfall rate?
    10·2 answers
  • Please, please, please help me!!!!!!
    9·1 answer
  • I WILLL GIVE BRAINLYEST!!!
    14·1 answer
  • An inductor, battery, resistance, and ammeter and switch are connected in series. If the switch, initially open, is now closed,
    15·1 answer
  • 2) __________ are chemical messengers produced by the endocrine system and released into the bloodstream.
    9·2 answers
  • The graph describes the motion of an object.
    11·1 answer
  • What happens to the period of the motion when the spring constant increases? Does it increase, decrease, or stay the same?
    8·1 answer
  • A diffraction-limited laser of length L and aperture diameter 0.50 cm generates light of wavelength 700nm . If the beam is direc
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!