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
andrey2020 [161]
3 years ago
6

A ball is thrown vertically upwards. It returns 6s later. Calculate : (1) the greatest height reached by the ball, and (2) the i

nitial velocity of the ball. (Take g=9.8m/s2) ​
Physics
1 answer:
dsp733 years ago
6 0

Answer:

greatest displacement = 44.1m

initial velocity= 29.4m/s

Explanation:

Greatest displacement

s=1/2at^2

= (9.8/2 ×9)m

= 44.1m

initial velocity

s=ut-1/2at^2

44.1= 3u -(1/2×9.8×9)

44.1=3u-44.1

3u=88.2

u=29.4m/s

You might be interested in
The adjustments that your eyes make as they look from objects near to objects far away or from objects far away to objects close
Hatshy [7]

Answer:

Oculomotor depth cues is based on two things convergence and accommodation,for the eyes to see near by things within 25cm near point we look inwards at this point the muscles holding the lens tighten up to see near by things unlike when we see far things we tend to look outwards with our eye muscles relaxing.

6 0
3 years ago
Why? I need some help I would like at least 1 answer <br><br><br> Thanks,<br> Vishnu
siniylev [52]
I think the 3rd one is the answer
8 0
3 years ago
A projectile is launched horizontally from a 20-m tall edifice with a vox of 25 m/s. How long will it take for the projectile to
NISA [10]

Answer:

a) First let's analyze the vertical problem:

When the projectile is on the air, the only vertical force acting on it is the gravitational force, then the acceleration of the projectile is the gravitational acceleration, and we can write this as:

a(t) = -9.8m/s^2

To get the vertical velocity we need to integrate over time to get:

v(t) = (-9.8m/s^2)*t + v0

where v0 is the initial vertical velocity because the object is thrown horizontally, we do not have any initial vertical velocity, then v0 = 0m/s

v(t) = (-9.8m/s^2)*t

To get the vertical position equation we need to integrate over time again, to get:

p(t) = (1/2)*(-9.8m/s^2)*t^2 + p0

where p0 is the initial position, in this case is the height of the edifice, 20m

then:

p(t) = (-4.9m/s^2)*t^2+ 20m

The projectile will hit the ground when p(t) = 0m, then we need to solve:

(-4.9m/s^2)*t^2+ 20m = 0m

20m = (4.9m/s^2)*t^2

√(20m/ (4.9m/s^2)) = t = 2.02 seconds

The correct option is a.

b) The range will be the total horizontal distance traveled by the projectile, as we do not have any horizontal force, we know that the horizontal velocity is 25 m/s constant.

Now we can use the relationship:

distance = speed*time

We know that the projectile travels for 2.02 seconds, then the total distance that it travels is:

distance = 2.02s*25m/s = 50.5m

Here the correct option is a.

c) Again, the horizontal velocity never changes, is 25m/s constantly, then here the correct option is option b. 25m/s

d) Here we need to evaluate the velocity equation in t = 2.02 seconds, this is the velocity of the projectile when it hits the ground.

v(2.02s) =  (-9.8m/s^2)*2.02s = -19.796 m/s

The velocity is negative because it goes down, and it matches with option d, so I suppose that the correct option here is option d (because the sign depends on how you think the problem)

4 0
3 years ago
An upright object 2.80 cm tall is placed 16.0 cm away from the vertex of a concave mirror with a center of curvature of 24.0 cm.
horrorfan [7]

Answer:

f = 12 cm

Explanation:

<u>Center of Curvature</u>:

The center of that hollow sphere, whose part is the spherical mirror, is known as the ‘Center of Curvature’ of  mirror.

<u>The Radius of Curvature</u>:

The radius of that hollow sphere, whose part is the spherical mirror, is known as the ‘Radius of Curvature’ of  mirror. It is the distance from pole to the center of curvature.

<u>Focal Length</u>:

The distance between principal focus and pole is called ‘Focal Length’. It is denoted by ‘F’.

The focal length of the spherical (concave) mirror is approximately equal to half of the radius of curvature:

f = \frac{R}{2}

where,

f = focal length = ?

R = Radius of curvature = 24 cm

Therefore,

f = \frac{24\ cm}{2}

<u>f = 12 cm</u>

8 0
2 years ago
A 10n falling object encounters 4n of air resistance. what is the net force on the object?
Margaret [11]
It would be 6n down.
5 0
3 years ago
Other questions:
  • Which quantity can be calculated using the equation E = mc2?
    5·2 answers
  • Martha is cycling at a speed of 20 kilometers per hour. How long will it take her to cover a distance of 60 kilometers? speed=di
    11·2 answers
  • What is the pressure of a 300 lb. object on a 100 sq. in. area?
    11·1 answer
  • Which subatomic particles have an electrical charge?
    11·2 answers
  • Two spheres of the same size and mass roll down an incline. Sphere A is hollow and Sphere B is solid with uniform density. Which
    15·1 answer
  • On a safari, a team of naturalists sets out toward a research station located 4.63 km away in a direction 38.7 ° north of east.
    14·1 answer
  • PLEASE HELP :/
    9·1 answer
  • What type of reaction is being shown in this energy diagram?
    12·1 answer
  • Resolve the weight of the box to find the component of the weight acting parallel to the slope.
    6·1 answer
  • Gerard is measuring the speed of a remote-controlled airplane. He measures that the airplane travels 110 m in 5.4 seconds, givin
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!