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
DerKrebs [107]
4 years ago
5

After catching the ball, Sarah throws it back to Julie. However, Sarah throws it too hard so it is over Julie's head when it rea

ches Julie's horizontal position. Assume the ball leaves Sarah's hand a distance 1.5 meters above the ground, reaches a maximum height of 8 m above the ground, and takes 1.619 s to get directly over Julie's head. What is the speed of the ball when it leaves Sarah's hand?
Physics
1 answer:
blsea [12.9K]4 years ago
4 0

Answer:

Vo=20.2m/s

Explanation:

We can calculate both components of initial velocity and the use them to calculate the speed as \sqrt{V_{ox}^{2}+V_{oy}^{2}}

From the vertical movement to the maximum height:

V_{fy}=V_{oy}-g*t  since V_{fy}=0

V_{oy}=g*t=16.19m/s

Now, from the horizontal movement, also to the point of maximum height:

Y_{f}=Y{o}+V_{oy}*t-\frac{g*t^{2}}{2}  Solving for V_{oy}

V_{oy}=12.1m/s

Finally we calculate the magnitude of the new vector:

V_{o}=\sqrt{V_{ox}^{2}+V_{oy}^{2}}=20.2m/s

You might be interested in
A sphere of uniform density with mass 21 kg and radius 0.8 m is spinning, making one complete revolution every 0.8 s. the center
kompoz [17]
Using the equation;
TE = 1/2mv^2(1+2); where k = 2/5 for a solid sphere; V is the velocity, and m is the mass.
Total energy = 0.5 × 21 × 8² (7/5)
                    = 940.8 J
The rotational kinetic energy of the sphere is 940.8 J

8 0
3 years ago
A billiard ball moving at 6.00 m/s strikes a stationary ball of the same mass. after the collision, the first ball moves at 5.39
kodGreya [7K]
<span>To do this question, we need to know that momentum is conserved, meaning the overall velocity of the two balls has to be the same before and after the collision.  </span>

<span>After collision... </span>

<span>Ball 1: 4.33m/s *cos 30 = 3.75 m/s (x-component) </span>
<span>4.33m/s * sin 30 = 2.165 m/s ( y-component) </span>

<span>Ball 2 (struck ball): 5 m/s - 3.75m/s = 1.25 m/s (x-component)  </span>
<span>-2.165 m/s (y-component) note: it has to be in the opposite direction to conserve momentum </span>

<span>tan-1(2.165/1.25) = 60 degrees </span>
<span>Struck ball's velocity = sqrt(1.25^2 + 2.165^2) = 2.5 m/s at 60 degree with respect to the original line of motion.  </span>

<span>Hope you understand!</span>
5 0
3 years ago
Read 2 more answers
A woman lives on the eighth floor of an apartment building. She works in a high-rise office building 6.5 blocks away from her ap
san4es73 [151]

Answer:

b)   d = 997.9 m ,  c) D = (952.9 i ^ +45 k ^) m ,  D = 953.6 m and θ = 2.7º

Explanation:

In this exercise we must add the distance traveled, remembering that the displacement is a vector and the distance a scalar.

a) The displacement scheme is the woman walks in her building A to descend to the lower floor 4.0 m, we assume that this includes the vertical displacement, until reaching the street level, the displacement is vertical in this part.

Being on the street, she travels the 6.5 blocks to reach the building where she works, they indicate that each block is 146.6 m, this movement is horizontal.

Upon reaching building B, she goes up to his office on the 14th floor where she travels 5.5m on each floor, it is assumed that the distance to go up to the upper floor is included, this displacement is vertical

b and c) Let's find the distance traveled and the displacement

in building A

                          Zₐ = 8 * 4.0

                          Zₐ = -32.0 m k ^

the vector k ^ indicates that the displacement is vertical and the negative sign that it is descending

on the street

                        X_{ab} = 6.5 146.6

                        X_{ab} = 952.9 m i ^

the vector i ^ indicates that the displacement is the x-axis, we assume that the axis is in the direction of the displacement

in building B

                         Z_{b} = 14 * 5.5

                         Z_{b} = 77 m k ^

displacement in the vertical axis and in the positive direction

now we calculate the distance traveled,

               d = Zₐ + X_{ab} + Z_{b}

               d = -32 + 952.9 + 77

               d = 997.9 m

note that this value is a scalar

Let's calculate the displacement,

Z axis

           Z_{total} = Zₐ +  Z_{b}

           Z_{total} = -32 + 77

          Z_{total} = 45 m k ^

X axis

           X_{total} = X_{ab}

           X_{total} = 952.9 m i ^

we can give the result in two ways

a) D = X_total i ^ + Z_total k ^

    D = (952.9 i ^ +45 k ^) m

b) in module form and angles

Let's use the Pythagorean theorem

     D² = X_{total}^2 + Z_{total}^2

     D = √(952.9² + 45²)

     D = 953.6 m

We use trigonometry

     tan θ = Z / X

     θ = tan⁻¹ (Z / X)

     θ = tan⁻¹ (45 / 952.9)

     θ = 2.7º

this angle is measured from the positive side of the x axis towards the z axis

6 0
3 years ago
which observation about the Mid-Atlantic Ridge region provides the best evidence of the seafloor has been spreading over for mil
Kitty [74]

Magnetic stripes on the sea floor

Explanation:

The observation of magnetic stripes patterns at the region of the Mid-Atlantic Ridge galvanized the evidence that sea floor spreading has been on for several millions of years.

  • Geomagnetic field of the earth is similar to that of bar magnet having the north and south pole.
  • It originates from the movement of iron-nickel within the outer core.
  • This geomagnetic field causes the magnetization of magnetic minerals in rock.
  • When freshly formed magma is brought to the surface at the mid oceanic ridge area, the prevailing magnetic field causes the magnetic minerals in the magma to cool in such a way that they align their domains to that of the field.
  • The magnetic field of the earth can reverse and take different geometry. Sometimes, its intensity is very strong and at other times it is weak.
  • The magnetic minerals in melts bear these records.
  • As new materials are brought up, they get magnetized.

Learn more:

Sea floor spreading brainly.com/question/9912731

#learnwithBrainly

8 0
3 years ago
Look at the diagram. What is the net force acting on the object?
nlexa [21]
The answer would be A
5 0
3 years ago
Read 2 more answers
Other questions:
  • Discuss in detail, one way in which atomic nuclear decay takes place. What is the significance of atomic nuclear decay? Analyze
    14·1 answer
  • A race car starting from rest accelerates uniformly at a rate of 4.90 meters per squared. What is the cars speed after it has tr
    7·1 answer
  • A metallic laboratory spring is typically 5.00 cm long and 0.150 cm in diameter and has 50 coils.
    15·1 answer
  • If you are traveling at 75 km/h how long will it take to travel 32 km?
    6·1 answer
  • Which force does not operate at a distance of 1 m?
    10·2 answers
  • 13. You throw a ball vertically upward, and as it leaves your hand, its speed is 37.0 m/s. How long (in s) does the ball take to
    12·1 answer
  • A bird flaps its wings 8 times per second. what is the frequency of the birds wing flapping?
    14·2 answers
  • PLEASE WRITE ME A 2 PARAGRAPH ESSAY ABOUT GENE POOLS!!! ALOT OF POINTS!!!!
    7·1 answer
  • A material that provides resistance to the flow of electric current is called a(n):
    10·1 answer
  • Which type of lens is shown in the picture below?<br> plane<br> refractional<br> concave
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!