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
drek231 [11]
3 years ago
7

A physics student stands on a cliff overlooking a lake and decides to throw a softball to her friends in the water below. She th

rows the softball with a velocity of 21.5 m/s at an angle of 33.5∘ above the horizontal. When the softball leaves her hand, it is 13.5 m above the water. How far does the softball travel horizontally before it hits the water?
Physics
1 answer:
aliina [53]3 years ago
3 0

Answer:

58.5 m

Explanation:

First of all, we need to find the total time the ball takes to reach the water. This can be done by looking at the vertical motion only.

The initial vertical velocity of the ball is

u_y = u sin \theta

where

u = 21.5 m/s is the initial speed

\theta=33.5^{\circ} is the angle

Substituting,

u_y = (21.5) sin 33.5^{\circ} =11.9 m/s

The vertical position of the ball at time t is given by

y = h + u_y t + \frac{1}{2}gt^2

where

h = 13.5 m is the initial heigth

g = -9.8 m/s^2 is the acceleration of gravity (negative sign because it points downward)

The ball reaches the water when y = 0, so

0 = h + u_yt +\frac{1}{2}gt^2\\0 = 13.5 +11.9 t - 4.9t^2

Which gives two solutions: t = 3.27 s and t = -0.84 s. We discard the negative solution since it is meaningless.

The horizontal velocity of the ball is

u_y = u cos \theta = (21.5) cos 33.5^{\circ} =17.9 m/s

And since the motion along the horizontal direction is a uniform motion, we can find the horizontal distance travelled by the ball as follows:

d= u_x t = (17.9)(3.27)=58.5 m

You might be interested in
Which statement describes a force acting on an object?
Aleonysh [2.5K]

Answer: B. A magnet pulls a nail towards it

Explanation: Out of the list of answers, this is the only answer where a force is acting on an object. the act of the magnet pulling on the nail is the force, and the nail is the object.

7 0
3 years ago
5. Which organisms are used to manufacture human insulin?
earnstyle [38]
The answer is going to be C, Bacteria. Therefore the organisms that are used to manufacture human insulin would be bacteria.
6 0
3 years ago
Two spacecraft are both 10 million kilometers from a star. The total power output of the star is 4 x 1025 W. Spacecraft 1 has a
Ksenya-84 [330]

The concept of power is given by the relationship between intensity and area, that is to say that power is defined as

P = A*I

Our values are given under the condition of,

r_1 = 18m

r_2 = m

The power is proportional to the Area, and in turn, we know that the Area of a circle is the product between \pi  times the radius squared, therefore the power is proportional to the radius squared.

\text{Power} \propto r^2

For both panels we would have to

\frac{\text{Power by panel 1}}{\text{Power by panel 2}} = \frac{r_1^2}{r_2^2}

\frac{P_1}{P_2} = (\frac{18}{6})^2

\frac{P_1}{P_2} = 9

Therefore the correct option is option C.9

5 0
3 years ago
Read 2 more answers
Find the velocity, acceleration, and speed of a particle with the given position function. r(t = t2i 6tj 4 ln t k
artcher [175]
1st derivative gives velocity;
d r(t)/ dt = 2t i + 6 j + 4/t k

2nd derivative gives acceleration;
d^2 r(t)/ dt^2 = 2 i - 4/ t^2

Speed ;
Square root of (4 t^2 + 36 + 16/ t^2)

For a given time, like 2 seconds, t will be 2. And answer of speed will be scalar.
6 0
3 years ago
Which situation would create a field like the one shown here?
kiruha [24]
D. Interaction between a magnetic South Pole and a copper bar
7 0
3 years ago
Other questions:
  • A ball is thrown horizontally from the roof of a building 7.8 m tall and lands 9.5 m from the base. what was the ball's initial
    8·1 answer
  • Research is being done on the use of radio waves in destroying cancer cells. What type of frequency would be best used in this t
    8·2 answers
  • Examine the scenario.
    14·2 answers
  • "The distance between the front and rear wheels of a 2280 kg car is 3.15 m. The car’s center of gravity lies in the middle of th
    14·1 answer
  • A circuit has a known resistance of 5 Ohms. An ammeter in the circuit gives a reading of 5 Amps. What is the Voltage of the circ
    14·1 answer
  • 10. A triply ionized beryllium atom is in the ground state. It absorbs energy and makes a transition to the n = 5 excited state.
    8·1 answer
  • ____________ is the number of complete movements of a wave per second.
    5·2 answers
  • A straight wire in a magnetic field experiences a force of 0.026 N when the current in the wire is 1.5 A. The current in the wir
    7·1 answer
  • A 10kg toy truck has a 5kg toy car at rest. If the toy truck was moving at 3 m/s before the collision and carries that car with
    13·2 answers
  • What is the relationship between the perimeter and the side length of anequilateral triangle ?
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!