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
goldfiish [28.3K]
3 years ago
15

A ball rolls of a desk a speed of 3.0m/s and lands 0.40 seconds later

Physics
1 answer:
lilavasa [31]3 years ago
8 0

a) The horizontal distance covered by the ball is 1.2 m

b) The height of the desk is 0.784 m

c) The speed at the time of impact is 4.9 m/s

Explanation:

a)

We have to calculate how far from the base of the desk the ball lands, that is the horizontal distance covered by the ball during its motion.

The motion of the ball is a projectile motion and consists of two independent motions:

- A horizontal uniform motion at constant velocity, since no forces act along the horizontal direction

- A vertical accelerated motion with constant acceleration g=9.8 m/s^2 towards the ground, due to the force of gravity

In this part we are only interested in the horizontal motion. The horizontal velocity of the ball is constant and it is

v_x = 3.0 m/s

And the time of flight is

t = 0.40 s

Therefore, the horizontal distance covered is

d=v_x t = (3.0)(0.40)=1.2 m

b)

To find the height of the desk, we have to consider the vertical motion, which is a uniformly accelerated motion. Therefore, we can use the following suvat equation:

s=u_yt+\frac{1}{2}at^2

where:

s is the vertical displacement (= the height of the desk)

u_y=0 is the initial vertical velocity

a=g=9.8 m/s^2 is the acceleration of gravity

t = 0.40 s is the time of flight

Substituting,

s=0+\frac{1}{2}(9.8)(0.40)^2=0.784 m

c)

To find the speed of the ball at the impact, we have to calculate both the horizontal and vertical components of the velocity at the time of impact.

We already said that the horizontal component is constant:

v_x = 3.0 m/s

While the vertical component is given by

v_y = u_y + at

where

u_y = 0\\a=g=9.8 m/s^2\\t=0.40 s

So

v_y = 0+(9.8)(0.40)=3.9 m/s

So, the speed of the ball at the time of impact is:

v=\sqrt{v_x^2+v_y^2}=\sqrt{(3.0)^2+(3.9)^2}=4.9 m/s

Learn more about projectile motion:

brainly.com/question/8751410

#LearnwithBrainly

You might be interested in
This graph indicates that the kinetic energy of an object is increasing. What is the most reasonable explanation for this observ
soldi70 [24.7K]

B) The object's velocity doubled.

Explanation:

The graph is missing: find it in attachment.

The kinetic energy of an object is the energy possessed by the object due to its motion. It is calculated as

K=\frac{1}{2}mv^2

where

m is the mass of the object

v is the velocity of the object

We notice that:

  • The  kinetic energy is directly proportional to the mass
  • The kinetic energy is proportional to the square of the velocity

In the graph, one of the two quantities (either mass or speed) is represented on the x-axis, while the quantity on the y-axis is the kinetic energy.

First of all, we notice that the relationship is not linear: this means that the quantity on the x-axis cannot be the mass, so it must be the velocity.

Moreover, we notice that when the quantity on the x-axis increases from 1 to 2 (so, it doubles), the kinetic energy increases by a factor of 4. This means that the object's velocity has doubled, therefore

B) The object's velocity doubled.

Learn more about kinetic energy:

brainly.com/question/6536722

#LearnwithBrainly

5 0
3 years ago
The force of replusion between two like charged particles will increase if​
Alex_Xolod [135]

Answer:

The distance of separation is decreased

Explanation:

From Cuolomb's law, we know that the strength of charge is inversely proportional to the distance of separation between the charges. To mean that increasing the distance let's say from 2m to 3 m would mean initial strength getting form 1/4 to 1/9 which is a decrease. The vice versa is true hence the force of repulsion can increase only when we decrease the distance of separation.

7 0
3 years ago
A small object begins a free-fall from a height of =81.5 m at 0=0 s . After τ=2.20 s , a second small object is launched vertica
-BARSIC- [3]

Answer:

33.2 m

Explanation:

For the first object:

y₀ = 81.5 m

v₀ = 0 m/s

a = -9.8 m/s²

t₀ = 0 s

y = y₀ + v₀ t + ½ at²

y = 81.5 − 4.9t²

For the second object:

y₀ = 0 m

v₀ = 40.0 m/s

a = -9.8 m/s²

t₀ = 2.20 s

y = y₀ + v₀ t + ½ at²

y = 40(t−2.2) − 4.9(t−2.2)²

When they meet:

81.5 − 4.9t² = 40(t−2.2) − 4.9(t−2.2)²

81.5 − 4.9t² = 40t − 88 − 4.9 (t² − 4.4t + 4.84)

81.5 − 4.9t² = 40t − 88 − 4.9t² + 21.56t − 23.716

81.5 = 61.56t − 111.716

193.216 = 61.56t

t = 3.139

The position at that time is:

y = 81.5 − 4.9(3.139)²

y = 33.2

7 0
3 years ago
Ran 300 meter in 40 seconds, what is the speed?
nignag [31]

Answer:

7.5

Explanation:

Speed= distance/ time

Speed= 300m/40sec

Speed= 7.5m/s

5 0
3 years ago
Something that might happen because of global warming is: __________. *
gogolik [260]

Answer:

melting polar icecaps seems the best, hopes this helps!

6 0
3 years ago
Other questions:
  • How do butterfly dest on there wings
    14·1 answer
  • A spring stores potential energy U0 when it is compressed a distance x0 from its uncompressed length.
    5·1 answer
  • If you designed a rollercoaster, how might you design it? Would you have friction?
    15·1 answer
  • Plz help me on science about cells
    7·1 answer
  • ¿Cuál es el valor de la sumatoria de todas las fuerzas que actúan sobre un cuerpo que está en equilibrio?
    12·1 answer
  • ITS EASY TRUST ME!!!!
    5·2 answers
  • Answer them all please!!
    9·1 answer
  • An B flat is played on a french horn, whose frequency is 466Hz.
    8·2 answers
  • What can you conclude about the velocity of the object on the graph below
    6·1 answer
  • Question # 6
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!