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
AlexFokin [52]
3 years ago
6

An object is propelled straight up from ground level with an initial velocity of 48 feet per second. Its height at time t is mod

eled by , where the height, s(t), is measured in feet and the time, t, is measured in seconds. a. What is the maximum height of the object and when does it occur? b. When does the object hit the ground? c. During what time interval is the height over 32 feet? Please show your work (i.e. don’t just depend on your graphing calculator!!)
Physics
1 answer:
Ket [755]3 years ago
8 0

Answer:

Explanation:

For a. its max height and when it occurs. First the max height. That's a y-dimension thing, and in the y-dimension we have this info:

v₀ = 48 ft/s

a = -32 ft/s/s

v = 0 (the max height of an object occurs when the final velocity of the object is 0). Use the following equation for this part of the problem:

v² = v₀² + 2aΔx and filling in:

0=48^2+2(-32)Δx and

0 = 2300 - 64Δx and

-2300 = -64Δs so

Δx = 36 feet.

Now for the time it takes to get to this max height. Final velocity is still 0 here, but the equation is a different one for this part of the problem. Use:

v = v₀ + at and filling in:

0 = 48 - 32t and

-48 = -32t so

t = 1.5 sec.  That's part a. Onto part b:

The object hits the ground when its displacement, Δx, is 0. Use this equation for this problem:

Δx = v₀t + \frac{1}{2}at^2 and filling in:

0=48t+\frac{1}{2}(-32)t^2 and

0=48t-16t^2 and

0 = 16t(3 - t) so

t = 0 and t = 3.  t = 0 is before the object is propelled, so it makes sense that at 0 seconds, the object was still on the ground, right? Then at 3 seconds, it's back on the ground. (Isn't math just perfectly, beautifully sensible!?) Now onto part c:

We are looking for the time interval when the object is >32 feet. So we use the same equation we just used, but with an inequality instead of an equals sign:

48t+\frac{1}{2}(-32)t^2 >32 and get everything on one side and factor it again:

-16t^2+48t-32>0 and we find that

1 < t < 2 so the time interval is between 1 and 2 seconds that the object is over 32 feet in the air.

You might be interested in
a racing car undergoes a uniform acceleration of 4.00m/s2. if the net force causing the acceleration is 3.00 times 10^3 N, what
yKpoI14uk [10]

Answer: 750Kg

Explanation:

Recall that force is the product of the mass M, of an object moving at a uniform acceleration.

i.e Force = Mass x Acceleration

In this case, Mass = ?

Force = 3.00 x 10^3 N = (3.00 x 1000N)

= 3000N

Uniform acceleration = 4.00m/s^2

Force = Mass x Acceleration

3000N = Mass x 4.00m/s^2

Mass = (3000N/4.00m/s^2)

Mass = 750Kg (The SI unit of mass is kilograms)

Thus, the mass of the car is 750Kg

4 0
3 years ago
The opening to a cave is a tall, 30.0-cm-wide crack. A bat is preparing to leave the cave emits a 30.0 kHz ultrasonic chirp. How
Vlada [557]

Answer:

The value is  w =  7.54 \  m        

Explanation:

From the question we are told that

     The length of the crack is  a =  0.3 \  m

     The  frequency is  f =  30.0 \ kHz =  30 *10^{3} \  Hz

      The distance outside the cave that is being consider is  D =  100 \  m

      The speed of sound is v_s =  340 \  m/s

Generally the wavelength of the wave is mathematically represented as

        \lambda =  \frac{v}f}

=>     \lambda =  \frac{340 }{30*10^{3}}

=>     \lambda = 0.0113 \ m/s

Generally for a  single slit the path difference between the interference patterns of the sound wave and the center  is mathematically represented as  

          y =  \frac{ n *  \lambda * D}{a}

=>     y =  \frac{ 1  *  0.0113 * 100}{0.3}

=>     y = 3.77 \  m

Generally the width of the sound beam is mathematically represented as

         w =  2 *  y

=>      w =  2 *  3.77

=>      w =  7.54 \  m        

4 0
3 years ago
A boy throws a ball with an initial velocity of 19.6 m/s. What maximum height does the ball reach?
Wewaii [24]
<h2>Hello!</h2>

The answer is: 19.59 m

<h2>Why?</h2>

Since there is no information about the launch type, we can assume that the ball is thrown vertically upward.

When the ball reaches the maximum height, just at that moment, the velocity turns to 0, and after that moment, the ball starts falling, so:

We will use the following formula:

Vf^2=Vi^2+2*g*s

Where:

Vf= Final velocity = 0

Vi= Initial velocity = \frac{19.6m}{s}

g = Gravity Acceleration = \frac{9.81m}{s^{2} }

s = Traveled distance

0=19.6^2+2*-9.81*s\\s=\frac{19.6^2}{2*9.81}=\frac{384.16}{19.62}=19.59m

Have a nice day!

8 0
3 years ago
A sound wave has a frequency of 425 hz. what is the period of this wave? 0.00235 seconds 0.807 seconds 425 seconds 850 seconds
77julia77 [94]

The period of the sound wave at the given frequency is determined as 0.00235 second.

<h3>Period of the sound wave</h3>

The period of the sound wave at the given frequency is calculated as follows;

Period is reciprocal of frequency.

T = 1/f

T = 1/425

T = 0.00235 second

Thus, the period of the sound wave at the given frequency is determined as 0.00235 second.

Learn more about period here: brainly.com/question/10428039

#SPJ1

3 0
1 year ago
Inez uses hairspray on her hair each morning before going to school. The spray spreads out before reaching her hair partly becau
Tamiku [17]

Answer:

7.0\cdot 10^{-13}C

Explanation:

The magnitude of the electrostatic force between two charged objects is

F=k\frac{q_1 q_2}{r^2}

where

k is the Coulomb's constant

q1 and q2 are the two charges

r is the separation between the two charges

The force is attractive if the charges have opposite sign and repulsive if the charges have same sign.

In this problem, we have:

r=0.070 cm =7\cdot 10^{-4} m is the distance between the charges

q_1=q_2=q since the charges are identical

F=9.0\cdot 10^{-9}N is the force between the charges

Re-arranging the equation and solving for q, we find the charge on each drop:

F=\frac{kq^2}{r^2}\\q=\sqrt{\frac{Fr^2}{k}}=\sqrt{\frac{(9.0\cdot 10^{-9})(7\cdot 10^{-4})^2}{8.99\cdot 10^9}}=7.0\cdot 10^{-13}C

8 0
3 years ago
Other questions:
  • Whats the Independent and Dependent Variables
    12·1 answer
  • joe forgot his homework at home.he runs home to get it.he accelerates from 0 to 15m/s in 5 seconds,runs at 15m/s for 50 seconds,
    9·1 answer
  • The (nonconservative) force propelling a 1.50 × 103-kg car up a mountain road does 4.70 × 106 J of work on the car. The car star
    14·1 answer
  • You are in your car at rest when the traffic light turns green. You place your coffee cup on the horizontal dash and hit the gas
    9·1 answer
  • The process of bringing a complaint and filing an answer is known as the _____. a. Trials b. Coercions c. Pleadings d. Countercl
    10·2 answers
  • Why can you not put diesel in a regular car?
    6·2 answers
  • In a “minute to win it” game, cards are placed between cups to stack them. The contestant then pulls the card out in hopes that
    9·2 answers
  • Which month has an average low of 26 degrees Fahrenheit​
    14·1 answer
  • 5. the combustion of a single molecule of methane produces about 10 ev of energy. a methane molecule has a mass of 16 amu. the f
    7·1 answer
  • 5.1 What is the nucleus composed of ?
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!