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
RUDIKE [14]
2 years ago
15

A ball is thrown from a top of a building of height 20m. If the initial velocity of the ball is 15m/s at 370 above the horizonta

l find, a) the velocity of the ball at 2s. b) the position at which the ball strike the ground.​
Physics
1 answer:
Lesechka [4]2 years ago
6 0

Explanation:

Givens:

h = 20 \: m

v _{ix} = 15 \cos(37)  = 11.97

v _{iy} = 15 \sin(37)  = 9.03

a _{y} =  - 9.8

Let t=2 be the final velocity. Since Velocity stays the same horizontal , acceleration due to gravity changes the vertical direction

Use this equation

v _{y} = v _{iy} + a _{y}(t)

Plug in the knowns

v _{y} = 15 \sin(37)  +2 ( - 9.8)

v _{y} =   - 10.57

So the velocity in the y direction at 2 seconds is -10.57

The velocity in the x direction at 2 seconds is 11.97

Use the Pythagorean theorem to find the total velocity

v =  \sqrt{( - 10.57) {}^{2} + (11.97) {}^{2}  }

v = 15.97

b. The range at which it strike the ground.

We need to find when the velocity at the top is zero.

Using the y direction,

0 = v \sin( 37 )  - 9.8(t)

t = 0.921

Next, find the height of the max.

h =  \frac{1}{2} ( 9.8)(0.921) {}^{2}  = 4.16

So the total distance is 4.16+20= 24.16

Next to find the total time it falls

24.16 =  \frac{1}{2} (9.8) {t}^{2}

t = 2.2

So our total flight time is

3.141

Range is

v \cos(37) (3.141) = 37.63

You might be interested in
A 15 W electric shaver is used for 3 minutes. How much energy does it use in joules?​
borishaifa [10]
P=change in E/t
Change in E=p*t
=15*3
=45

The answer is 45J.
3 0
3 years ago
Calculate the kinetic energy of a motorcycle of mass 60kg travelling at a velocity of 40km/h​
ELEN [110]

Answer:

1848.15J

Explanation:

KE =1/2 mv^2

Mass = 60kg, velocity =40km/h =11.11m/s

Hence

KE =30 x(11.1)^2 /2 = 1848.15J

5 0
3 years ago
A pendulum of length L is suspended from the ceiling of an elevator. When the elevator is at rest the period of the pendulum is
Stolb23 [73]
<h2>Option A is the correct answer.</h2>

Explanation:

When an elevator moves upward with consonant acceleration a, the overall acceleration on the body is given by

                        a' = a + g

So acceleration of pendulum is a + g.

We have equation for period of simple pendulum

                     T=2\pi \sqrt{\frac{l}{a'}}

In normal case a' = g here a' is more.

From the equation we can see that period of simple pendulum is inversely proportional to square root of acceleration.

Since acceleration increases period decreases.

Option A is the correct answer.

8 0
3 years ago
Read 2 more answers
Viruses are hard to get rid of
tekilochka [14]

The answer is D, they reproduce quickly.

4 0
3 years ago
Read 2 more answers
The body needs small amounts of ________ to help enzymes break down proteins.
Inessa [10]

Answer:

I would say vitamin B-6

Explanation:

it is also known as pyridoxine. it helps ebzymes break down protein and carry the dismantled amino acids to the blood stream

Hope this helps ✌✌

4 0
3 years ago
Read 2 more answers
Other questions:
  • A runaway train with a mass of 6,251 kg is approaching the end of the line at a speed of 27 m/s. The end of the line has a massi
    8·1 answer
  • The organization of former British colonies that includes Canada, India, Pakistan, and other countries is called the __________.
    9·2 answers
  • A roulette wheel with a 1.0m radius reaches a maximum angular speed of 18 rad/s before it stops 35 revolutions ( 220 rad ) after
    8·1 answer
  • Fariza wears a red hat in her school play. On stage, she is lit by a spotlight shining only green light. When our eyes receive n
    10·1 answer
  • A wire of length L and cross-sectional area A has resistance R.
    13·1 answer
  • Why did boy (the observer) hear the pitch of the sound change? What does this tell us about the frequency of the sound? Support
    10·1 answer
  • When the forces acting moving body are balanced the net force becomes zero. As a result the body will:
    11·1 answer
  • A 175-kg roller coaster car starts from rest at the top of an 18.0-m hill and rolls down the hill, then up a second hill that ha
    8·1 answer
  • How does the declining biodiversity affect us?
    6·2 answers
  • 0. 85 kg of lead, specific heat 128 J/kgC, is heated from 50 C to 95 C. How much heat energy did the sample absorb?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!