answer.
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
levacccp [35]
2 years ago
11

Use the formula h = −16t2 + v0t. (if an answer does not exist, enter dne.) a ball is thrown straight upward at an initial speed

of v0 = 56 ft/s. (a) when does the ball initially reach a height of 40 ft?
Physics
1 answer:
makkiz [27]2 years ago
3 0
Using the given formula with v0=56 ft/s and h=40 ft 
h = -16t2 + v0t  
40 = -16t2 + 56t 
16t2 - 56t + 40 = 0  
Solving the quadratic equation:  
t= (-b+/-(b^2-4ac)^1/2)/2a = (56+/-((-56)^2-4*16*40)^1/2)/2*16 = (56 +/- 24) / 32 
 We have two possible solutions  
t1 = (56+24)/32 = 2.5 
t2 = (56-24)/32 = 1  
So initially the ball reach a height of 40 ft in 1 second.
You might be interested in
Submarine a travels horizontally at 11.0 m/s through ocean water. it emits a sonar signal of frequency f 5 5.27 3 103 hz in the
xeze [42]
Velocity of submarine A is vs = 11.0m/s
frequency emitted by submarine A. F = 55.273 × 10∧3HZ
Velocity of submarine B = vO = 3.00m/s
The given equation is
f' = ((V + vO) ((v - vS)) × f
The observer on submarine detects the frequency f'.
The sign of vO should be positive as the observer of submarine B is moving away from the source of submarine A.
The speed of the sound used in seawater is 1533m/s
The frequency which is detected by submarine B is 
fo = fs (V -vO/ v +vs)
= 53.273 × 10∧3hz) ((1533 m/s - 4.5 m/s)/ (1533 m/s +11 m/s)
fo = 5408 HZ
6 0
2 years ago
In coordinates with the origin at the barn door, the cow walks from x 0 to x 6.9 m as you apply a force with x component Fx 320.
Stella [2.4K]

Answer:

-209.42J

Explanation:

Here is the complete question.

A balky cow is leaving the barn as you try harder and harder to push her back in. In coordinates with the origin at the barn door, the cow walks from x = 0 to x = 6.9 m as you apply a force with x-component Fx=−[20.0N+(3.0N/m)x]. How much work does the force you apply do on the cow during this displacement?

Solution

The work done by a force W = ∫Fdx since our force is variable.

Since the cow moves from x₁ = 0 m to x₂ = 6.9 m and F = Fx =−[20.0N+(3.0N/m)x] the force applied on the cow.

So, the workdone by the force on the cow is  

W = ∫₀⁶°⁹Fx dx = ∫₀⁶°⁹−[20.0N+(3.0N/m)x] dx

= ∫₀⁶°⁹−[20.0Ndx - ∫₀⁶°⁹(3.0N/m)x] dx

= −[20.0x]₀⁶°⁹ - [3.0x²/2]₀⁶°⁹

= -[20 × 6.9 - 20 × 0] - [3.0 × 6.9²/2 - 3.0 × 0²/2]

= -[138 - 0] - [71.415 - 0] J = (-138 - 71.415) J

= -209.415 J ≅ -209.42J

5 0
2 years ago
Boiling water in a pan is a good example of convection because___.
belka [17]
Convection means that hotter and less dense fluids have a tendency to rise while colder and more dense fluids sink.

The answer would be (A)
Hot water is denser than cold water and so hot water will be above the cold water.

:D
5 0
2 years ago
Read 2 more answers
A major league baseball pitcher throws a pitch that follows these parametric equations: x(t) = 142t y(t) = –16t2 + 5t + 5. The t
azamat

Answer:

(a) x'(t)= 142

(b) 142

(c) y'(t)= -32t+5

(d) 96.8 mph

(e) 0.426 s

(f) 0.061 rad

Explanation:

Velocity is a time-derivative of position.

(a) x(t) = 142t

x'(t)= 142

(b) Since x'(t)= 142 is independent of t, it follows it was constant throughout. Hence, at any point or time, the horizontal velocity is 142.

(c) y(t) = - 16t^2+5t+5

y'(t)= -32t+5

(d) When it passes the home plate, the ball has travelled 60.5 ft (from the question). This is horizontal, so it is equivalent to x(t).

x(t)= 142t = 60.5

t=\dfrac{60.5}{142}= 0.426.

In this time, the vertical velocity, y'(t) is

y(t)= -32\times0.426+5 = -8.632

The speed of the ball at thus point is s=\sqrt{142^2+(-8.632)^2}=142 ft/s

To convert this to mph, we multiply the factor 3600/5280

s=142\times\dfrac{3600}{5280}=96.8 \text{ mph}

(e) The time has been determined from (d) above.

t= 0.426

(f) This angle is given by

\theta=\tan^{-1}\dfrac{y'(t)}{x'(t)}

\theta=\tan^{-1}\dfrac{-8.632}{142}=\tan^{-1}-0.0607=3.47 (Note here we are considering the acute angle so we ignore the negative sign)

In radians, this is

\theta=3.47\times\dfrac{\pi}{180}=0.061 \text{ rad}

6 0
2 years ago
A container explodes and breaks into three fragments that fly off 120° apart from each other, with mass ratios 1: 4: 2. If the f
RSB [31]

Answer:

V₂ = 1.5 m/s

Explanation:

given,

speed of the first piece = 6 m/s

speed of the third piece = 3 m/s

speed of the second fragment = ?

mass ratios = 1 : 4 : 2

fragment break  fly off = 120°

α = β = γ  = 120°

sin α = sin β = sin γ = 0.866

using lammi's theorem

\dfrac{A}{sin\alpha}=\dfrac{B}{sin\beta}=\dfrac{C}{sin\gamma}

A,B and C is momentum of the fragments

\dfrac{m\times 6}{0.866}=\dfrac{4m\times v_2}{0.866}=\dfrac{2m\times 3}{0.866}

4 x V₂ = 2 x 3

V₂ = 1.5 m/s

3 0
2 years ago
Other questions:
  • Your boss asks you to design a room that can be as soundproof as possible and provides you with three samples of material. The o
    11·2 answers
  • This outlaw is executed by hanging "in the spring of '25" by
    10·1 answer
  • An apple falls from an apple tree growing on a 20° slope. The apple hits the ground with an impact velocity of 16.2 m/s straight
    12·1 answer
  • A person kicks a ball, giving it an initial velocity of 20.0 m/s up a wooden ramp. When the ball reaches the top, it becomes air
    12·1 answer
  • Why is it unwise to stir a pot of soup with a metal spoon?
    14·2 answers
  • You are attending a county fair with your friend from your physics class. While walking around the fairgrounds, you discover a n
    12·1 answer
  • What is the change in entropy of helium gas with total mass 0.135 kg at the normal boiling point of helium when it all condenses
    13·1 answer
  • Conduction of a nerve impulse would be the fastest in _________
    9·1 answer
  • To practice tactics box 13.1 hydrostatics. in problems about liquids in hydrostatic equilibrium, you often need to find the pres
    9·1 answer
  • A cyclist traveling at 5m/s uniformly accelerates up to 10 m/s in 2 seconds. Each tire of the bike has a 35 cm radius, and a sma
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!