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
Naddik [55]
3 years ago
10

A boy throws a rock with an initial velocity of 2.15 m/s at 30.0° above the horizontal. If air resistance is negligible, how lon

g does it take for the rock to reach the maximum height of its trajectory?
Physics
1 answer:
vladimir1956 [14]3 years ago
4 0

Answer:

t = 0.11 second

The time taken to reach the maximum height of the trajectory is 0.11 second

Explanation:

Taking the vertical component of the initial velocity;

Vy = Vsin∅

Initial velocity V = 2.15 m/s

Angle ∅ = 30°

Vy = 2.15sin30 = 2.15 × 0.5

Vy = 1.075 m/s

The height of the rock at time t during the flight is;

From the equation of motion;

h(t) = Vy×t - 0.5gt^2

g= acceleration due to gravity = 9.8m/s^2

Substituting the given values;

h(t) = 1.075t - 0.5(9.8)t^2

h(t) = 1.075t - 4.9t^2

The rock is at maximum height when dh/dt = 0;

dh(t)/dt = 1.075 - 9.8t = 0

1.075 - 9.8t = 0

9.8t = 1.075

t = 1.075/9.8

t = 0.109693877551 s

t = 0.11 second

The time taken to reach the maximum height of the trajectory is 0.11 second

You might be interested in
Assume that a 15-kg ball moving at 8 m/s strikes a wall perpendicularly and rebounds elastically at the same speed. What is the
Aleks [24]
I think u should follow the formulae F=MA. So I think the answer is 120N
5 0
3 years ago
A small branch is wedged under a 200 kg rock and rests on a smaller object. The smaller object is 2.0 m from the large rock and
Alexxandr [17]

Answer:

a

  F  =326.7 \ N

b

  M  = 6

Explanation:

From the question we are told that

          The mass of the rock is  m_r  =  200 \ kg

          The  length of the small object from the rock is  d  =  2 \ m

          The  length of the small object from the branch l  =  12 \ m

An image representing this lever set-up is shown on the first uploaded image

Here the small object acts as a fulcrum

The  force exerted by the weight of the rock is mathematically evaluated as

      W =  m_r *  g

substituting values

     W =   200 *  9.8

     W =   1960 \ N

 So  at  equilibrium the sum  of the moment about the fulcrum is mathematically represented as

         \sum  M_f  =  F * cos \theta *  l  -  W cos\theta  *  d =  0

Here  \theta is very small so  cos\theta  *  l  =  l

                               and  cos\theta  *  d  =  d

Hence

       F *   l  -  W  * d =  0

=>    F  = \frac{W * d}{l}

substituting values

        F  = \frac{1960 *  2}{12}

       F  =326.7 \ N

The  mechanical advantage is mathematically evaluated as

          M  = \frac{W}{F}

substituting values

        M  = \frac{1960}{326.7}

       M  = 6

6 0
3 years ago
Question 8 of 10
Marrrta [24]

Answer:

C

Explanation:

If the theory were to be proved you you need to repeat the experiment over and over again so that way you can prove that it is true wuth the same results.

3 0
3 years ago
Read 2 more answers
Found throughout the nervous system, __________ aid and support the function of neurons.
Nonamiya [84]

Answer:

Glia

Explanation:

8 0
2 years ago
Read 2 more answers
A wheelbarrow is a complex machine that combines which simply marchines?
koban [17]
It's most likely the combination of a bucket and the wheel. 
4 0
3 years ago
Read 2 more answers
Other questions:
  • Do deaf children go through the four stages of acquiring language? Use what you’ve read in the chapter to explain why or why not
    6·1 answer
  • A woman steps in front of a child to keep him from running off. which term best describes this example? negative work positive w
    9·2 answers
  • Un auto recorre una carretera en línea recta de 10km y tarda 8 minutos ¿Cual es su velocidad en km/h?
    14·1 answer
  • Two enery converrsation that take place when you warm a cup of cocoa in a microwave<br> Oven
    13·1 answer
  • What activity level should participants be in when exercising in their target heart rate zone
    9·1 answer
  • Which other subatomic particle has the same mass as a neutron
    7·2 answers
  • Un resorte se alarga 5 cm bajo la acción de una fuerza de 39,2 N. ¿Cuál es la constante del resorte? Si ahora la fuerza es 68,6
    10·1 answer
  • 4. How long would it take for a water balloon to fall 39 m if we dropped it starting from rest down an
    15·1 answer
  • Im so confused can someone help. I’ll give you BRAINLIETS
    12·1 answer
  • Item 4 A student conducts an experiment to determine how the temperature of water affects the time for sugar to dissolve. In eac
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!