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
Svetradugi [14.3K]
3 years ago
6

A football kicked in front of a goal post at an angle of 45 degree to the ground just clear the top by of the post 3m high. Calc

ulate the velocity of projection and the time taken to hit the ground again from the instant it was kicked.​
Physics
1 answer:
Firlakuza [10]3 years ago
7 0

Answer:

A. 10.84 m/s

B. 1.56 s

Explanation:

From the question given above, the following data were obtained:

Angle of projection (θ) = 45°

Maximum height (H) = 3 m

Acceleration due to gravity (g) = 9.8 m/s²

Velocity of projection (u) =?

Time (T) taken to hit the ground again =?

A. Determination of the velocity of projection.

Angle of projection (θ) = 45°

Maximum height (H) = 3 m

Acceleration due to gravity (g) = 9.8 m/s²

Velocity of projection (u) =?

H = u²Sine²θ / 2g

3 = u²(Sine 45)² / 2 × 9.8

3 = u²(0.7071)² / 19.6

Cross multiply

3 × 19.6 = u²(0.7071)²

58.8 = u²(0.7071)²

Divide both side by (0.7071)²

u² = 58.8 / (0.7071)²

u² = 117.60

Take the square root of both side

u = √117.60

u = 10.84 m/s

Therefore, the velocity of projection is 10.84 m/s.

B. Determination of the time taken to hit the ground again.

Angle of projection (θ) = 45°

Velocity of projection (u) = 10.84 m/s

Time (T) taken to hit the ground again =?

T = 2uSine θ /g

T = 2 × 10.84 × Sine 45 / 9.8

T = 21.68 × 0.7071 / 9.8

T = 1.56 s

Therefore, the time taken to hit the ground again is 1.56 s.

You might be interested in
List five (5) compounds h2o can form (10 points)
Elena-2011 [213]

Oxygen, hydrogen, sodium, chlorine, lead, iron. Hope this helps!!!


8 0
3 years ago
2. A proton and an electron are sitting 0.5m away from each other. What is the
Brrunno [24]

Answer:we can calculate the answer by the following formula;

Explanation:

3 0
3 years ago
A motorboat accelerates uniformly from a velocity of 6.5 m/s west to a velocity of 1.5 m/s west. If its acceleration was 2.7 m/s
expeople1 [14]

Answer:

<em>The motorboat ends up 7.41 meters to the west of the initial position </em>

Explanation:

<u>Accelerated Motion </u>

The accelerated motion describes a situation where an object changes its velocity over time. If the acceleration is constant, then these formulas apply:

\vec v_f=\vec v_o+\vec a.t

\displaystyle \vec r=\vec v_o.t+\frac{\vec a.t^2}{2}

The problem provides the conditions of the motorboat's motion. The initial velocity is 6.5 m/s west. The final velocity is 1.5 m/s west, and the acceleration is 2.7 m/s^2 to the east. Since all the movement takes place in one dimension, we can ignore the vectorial notation and work with the signs of the variables, according to a defined positive direction. We'll follow the rule that all the directional magnitudes are positive to the east and negative to the west. Rewriting the formulas:

v_f=v_o+a.t

\displaystyle x=v_o.t+\frac{a.t^2}{2}

Solving the first one for t

\displaystyle t=\frac{v_f-v_o}{a}

We have

v_o=-6.5,\ v_f=-1.5,\ a=2.7

Using these values

\displaystyle t=\frac{-1.5+6.5}{2.7}=1.852\ s

We now compute x

\displaystyle x=(-6.5)(1.852)+\frac{(2.7)(1.852)^2}{2}

x=-7,41\ m

The motorboat ends up 7.41 meters to the west of the initial position

5 0
3 years ago
Why do you think plants surround the seeds with a yummy fruit?
beks73 [17]

Answer:Cross-pollination is two plants that work together to pollinate and self-pollinate is when a flower pollinates itself. ... Why do you think plants surround the seeds with a yummy fruit? To protect the seeds so that they can reproduce. How is cross-pollination different from self-pollination?

Explanation:

4 0
3 years ago
I need help with this
fredd [130]
We have here what is known as parallel combination of resistors.

Using the relation:

\frac{1}{ r_{eff} } = \frac{1}{ r_{1} } + \frac{1}{ r_{2} } + \frac{1}{ r_{3} }.. . + \frac{1}{ r_{n} } \\
And then we can turn take the inverse to get the effective resistance.

Where r is the magnitude of the resistance offered by each resistor.

In this case we have,
(every term has an mho in the end)
\frac{1}{10000} + \frac{1}{2000} + \frac{1}{1000} \\ \\ = \frac{1}{1000} ( \frac{1}{10} + \frac{1}{2} + \frac{1}{1} ) \\ \\ = \frac{1}{1000} ( \frac{31}{20}) \\ \\ = \frac{31}{20000}

To ger effective resistance take the inverse:
we get,
\frac{20000}{31} \: ohm \\ = 645 .16 \: ohm

The potential difference is of 9V.

So the current flowing using ohm's law,

V = IR

will be, 0.0139 Amperes.
7 0
3 years ago
Other questions:
  • Tarzan (75 kg) swings from 4 metres high on a vine down to ground level and catches Jane (50 kg). How fast are they moving after
    9·1 answer
  • A student is conducting an experiment to determine how far a ball will roll down a ramp based on the angle of incline.
    5·2 answers
  • This is a type of symbiotic relationship where both organisms benefit. A) commensalism B) competition C) mutualism D) parasitism
    6·2 answers
  • Which of the following processes is not regarded as contributing to the creation of greenhouse gases? deforestation creating ele
    13·2 answers
  • Two small plastic spheres are given positive electrical charges. When they are 16.0 cm apart, the repulsive force between them h
    13·1 answer
  • A rifle is fired in a valley with parallel vertical walls. The echo from one wall is heard 1.55 s after the rifle was fired. The
    7·1 answer
  • What is the Principle of electric generator?
    12·2 answers
  • Calculate the average travel time for each distance, and then use the results to calculate.
    10·2 answers
  • What is the acceleration of a 150 kg object pushed with a force of 1000 N?
    11·1 answer
  • A snow ball is thrown upward at a speed of 27 m/s. How high is the snow ball 3.5 seconds later? Also, how fast is it moving at t
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!