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
Temka [501]
3 years ago
9

A ball is thrown upward with an initial velocity of 48 ft/s from a height 864 ft. h = -16t +48t +864 After how many seconds will

the ball reach the ground? (i.e. For what positive value of t is h=0?) ...?
Physics
1 answer:
neonofarm [45]3 years ago
6 0
0 = -16 t^2 + 48t  + 864  (Divide all by 16)

-t^2 + 3t  + 54

(t-9) (t+6) = 0

t = 9s
t = -6s

so the positive value would be : 9s

hope this helps


You might be interested in
A stone is dropped from the
ICE Princess25 [194]
  • Height=h=500m
  • Acceleration=g=10m/s^2
  • Initial velocity=u=0
  • Speed of sound=c=340m/s
  • TIME TAKEN BY STONE TO HIT WATER=t
  • Time taken by sound to hear back=T

Now

\\ \sf\longmapsto h=ut+\dfrac{1}{2}gt^2

\\ \sf\longmapsto h=0t+\dfrac{1}{2}10t^2

\\ \sf\longmapsto 500=5t^2

\\ \sf\longmapsto t^2=100

\\ \sf\longmapsto t=10s

Now

\\ \sf\longmapsto h=cT

\\ \sf\longmapsto T=\dfrac{h}{c}

\\ \sf\longmapsto T=\dfrac{500}{340}

\\ \sf\longmapsto T=1.47\approx 1.5s

Total time:-

\\ \sf\longmapsto T_{net}=t+T=10+1.5=11.5s

8 0
2 years ago
How is temperature related to the physical change of a substance?
WINSTONCH [101]
When you heat something of cool it down you don't change the substance you might change the why is looks, but it is still the same substance. For example you cool water to 0 degrees Celsius it turns into ice but it still is two parts hydrogen and one part oxygen H2O. Physical changes will change state and/or form but it will still be what it originally was on the molecular level. Hope that helped. 
8 0
3 years ago
Read 2 more answers
A 50.0-kg bungee jumper steps off a bridge with a light bungee cord tied to her and to the bridge. The unstretched length of the
lina2011 [118]

Answer:

The the analysis for the free fall part should be done under the constant acceleration.

Explanation:

In the given problem, the jumper is falling under the free fall. Since, no external force is acting on the body therefore, the fall will be under the action gravity only. also, the acceleration due to gravity is always constant.

Therefore, the the analysis for the free fall part should be done under the constant acceleration.

8 0
3 years ago
A sound wave travels in air toward the surface of a freshwater lake and enters into the water. The frequency of the sound does n
Shkiper50 [21]

Answer:

Explanation:

velocity of sound in air at 20⁰C is 343 m /s

velocity of sound in water at 20⁰C is 1481 m /s

The wavelength of the sound is 2.86 m in the air so its frequency

= 343 / 2.86 = 119.93 .

This frequency of  119.93 will remain unchanged in water .

wavelength in water = velocity in water / frequency

= 1481 / 119.93

= 12. 35 m .

7 0
3 years ago
A bullet B of mass mB traveling with a speed v0 = 1400 m/s ricochets off a fixed steel plate A of mass mA. Let mA ≫ mB so that i
Greeley [361]

Answer:

Rebounce angle is 345°

Rebounce speed is 989.95m/s

Explanation:

Calculate the x  component of the velocity of the bullet before impact by using the following relation:

Vbx= Vb Cos thetha

Here,  is the initial velocity of the bullet, Vo = 1400m/s and is the incidence angle of the bullet.= theta = 15°

Substituting

Vbx = Cos15 ×1400 = 1352.30m/s

Calculate the y component using the relation:

Vby = Vo Sin theta

Vby = sin 15° × 1400

Vby = 362.35m/s

The rebounce angle = 360 - incidence angle

Rebounce angle =( 360 - 15)° = 345°

The rebound speed V' = Vby - Vbx

V' = (1352.30 - 362.35)m/s

V' = 989.95 m/s

5 0
4 years ago
Other questions:
  • a bicycle travels at a velocity of -2.33 m/s and has a displacement of -58.3 m. how much time did it take?
    9·1 answer
  • A 128.0-N carton is pulled up a frictionless baggage ramp inclined at 30.0∘above the horizontal by a rope exerting a 72.0-N pull
    5·1 answer
  • A string is attached to a vibrating machine that has a frequency of 120 Hz. The other end of the string is passed over a pulley
    6·1 answer
  • 50 POINTS PICTURE WITH QUESTION AND CHOICES BELOW
    12·2 answers
  • Which property describes the temperature at which a liquid changes to a gas?
    5·1 answer
  • Two adjoining plane mirrors are separated by an angle of 100°. Light is incident on the first mirror at an angle of 70°. The lig
    14·2 answers
  • A lightning flash may transfer up to 14 C of charge through a potential difference of 107 V
    10·1 answer
  • A fat person weighing 80 Kg falls on a concrete floor from 2m. If whole of the mechanical energy is converted into heat energy,
    11·1 answer
  • Find the potential energy of a 2 kg ball 15 m in the air.
    15·1 answer
  • SI UNIT OF GRAVITY is the​
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!