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
V125BC [204]
3 years ago
9

A ball rolls off the top of the roof of a building that is 13 meters tall. Calculate the amount of time it takes for it to hit t

he ground.
Physics
1 answer:
kramer3 years ago
5 0

Answer:

The ball takes $t=1 \cdot 917sec$ to hit the ground.

Explanation:

• The second equation of motion represents the total distances travelled by an object in a time interval of $\Delta t$ with an initial speed of $u$ and acceleration $a$.

• To find the time, ball takes to hit the ground, use the formula: $$s = ut + \frac{1}{2}a{t^2}$$

Where, $t$ is time, $u$ is initial velocity, $a$ is acceleration and$s$ is displacement.

• In this case, $a = g = 9 \cdot 8m/se{c^2}$.

• Placing the value of the given initial velocity, $u=0cm/s$ and displacement,$s = 13m$ in the above formula.

& \therefore s = ut + \frac{1}{2}g{t^2}  \\&  \Rightarrow 13 = 0 \cdot t + \frac{1}{2} \times 9 \cdot 8 \times {t^2}  \\

&  \Rightarrow 13 = 4 \cdot 9{t^2}  \\&  \Rightarrow {t^2} = \frac{{13}}{{4.9}}  \\&  \Rightarrow t = 1 \cdot 917sec \\\end{align}\]

• Hence, ball takes $t=1 \cdot 917sec$ to hit the ground.

Learn more about second equation of motion here:

brainly.com/question/19030143

You might be interested in
James is planning a science fair project on sound waves. He places an alarm inside a jar which he can remove the
ss7ja [257]

Answer:

D

Explanation:

this is simple, because when air is removed, means that there is no particles in the jar so vacuum is achieved, and when you can't hear a sound means that the sound couldn't travel through the vacuum. which means that sound cannot travel through vacuum,

as a result, sound requires a medium ( air) travel from one point to another.

hope it helps, if not please report it so that someone else gets to try it

7 0
3 years ago
What is the amount of work done when a force of 10N moves a 20kg mass of 8 meters?
Nataly_w [17]

Yo sup??

we should know that

work done=force*displacement

W=F.s

F=10 N

s=8 m

therefore

W=10*8

=80 N

Hope this helps.

3 0
3 years ago
A boy throws a baseball onto a roof and it rolls back down and off the roof with a speed of 4.05 m/s. If the roof is pitched at
AlekseyPX

(a) The time the baseball spends in the air is 0.92 s.

(b) The horizontal distance from the roof edge to the point where the baseball lands on the ground is 3.1 m.

<h3>Time spent in air by the baseball</h3>

h = vt - ¹/₂gt²

-2.1 = (4.05 x sin 34)t  - ¹/₂(9.8)(t²)

-2.1 = 2.26t - 4.9t²

4.9t² - 2.26t - 2.1 = 0

t = 0.92 s

<h3>Horizontal distance traveled by the baseball</h3>

R = Vx(t)

R = (4.05 x cos 34)(0.92)

R = 3.1 m

Thus, the time the baseball spends in the air is 0.92 s.

The horizontal distance from the roof edge to the point where the baseball lands on the ground is 3.1 m.

Learn more about horizontal distance here: brainly.com/question/24784992

#SPJ1

8 0
2 years ago
Suppose you are standing on top of a hemisphere of radius r and you kick a soccer ball horizontally such that it has velocity v.
Ksivusya [100]

|v| =\sqrt{ G \cdot M / r}, where

  • M the mass of the planet, and
  • G the universal gravitation constant.

Explanation:

Minimizing the initial velocity of the soccer ball would minimize the amount of mechanical energy it has. It shall maintain a minimal gravitational potential possible at all time. It should therefore stay to the ground as close as possible. An elliptical trajectory would thus be unfavorable; the ball shall maintain a uniform circular motion as it orbits the planet.

<em>Equation 1</em>  (see below) relates net force the object experiences, \Sigma F to its orbit velocity v and its mass m required for it to stay in orbit :

\Sigma F = m \cdot v^{2} / r <em>(equation 1)</em>

The soccer ball shall experiences a combination of gravitational pull and air resistance (if any) as it orbits the planet. Assuming negligible air resistance, the net force \Sigma F acting on the soccer ball shall equal to its weight, W = m \cdot g where g the gravitational acceleration constant. Thus

\Sigma F = W = m \cdot g <em>(equation 2)</em>

Substitute equation 2 to the left hand side of <em>equation 1</em> and solve for v; note how the mass of the soccer ball, m, cancels out:

m \cdot g = \Sigma F = m \cdot v^{2} / r \\ v^{2} = g \cdot r \\ |v| = \sqrt{g \cdot r} \; (|v| \ge 0) <em>(equation 3)</em>

<em>Equation 4 </em> gives the value of gravitational acceleration, g, a point of negligible mass experiences at a distance r from a planet of mass M (assuming no other stellar object were present)

g = G \cdot M/ r^{2} <em>(equation 4)</em>

where the universal gravitation <em>constant</em> G = 6.67408 \times 10^{-11} \cdot \text{m}^{3} \cdot \text{kg}^{-1} \cdot \text{s}^{-2}

Thus

\begin{array}{lll}|v| &=& \sqrt{g \cdot r}\\ & =&\sqrt{ G \cdot M / r}\end{array}

3 0
3 years ago
What is the magnitude of the electric field at a point that is 0.5m to the right of a small sphere with a net charge of -6.0x10-
zysi [14]

Answer:

lil durk a goat

Explanation:

8 0
2 years ago
Other questions:
  • Starting from rest, a disk takes 8 revolutions to reach an angular velocity ω at constant angular acceleration. how many additio
    11·1 answer
  • Describe the organization of our solar system
    14·2 answers
  • A machine produces a larger force than you exert to operate the machine. How does this input distance of the machine compare to
    10·1 answer
  • When plug prongs are connected to the metal case of an appliance, a part that should always be placed next to the case is a
    12·1 answer
  • A baseball of mass 0.25 kg is hit at home plate with a speed of 40 m/s. When it lands in a seat in the left-field bleachers a ho
    15·1 answer
  • A boy having 0.2kg toy tied with a sting, having force 2N, angle 60º displaces it 5 m. What is the work done?
    10·1 answer
  • Estimate the force a person must exert on a massless string attached to a 0.15 kg ball to make the ball revolve in horizontal ci
    10·1 answer
  • todos los cuerpos pueden estar sobre la tierra por la fuerza de gravedad .cuando nos caemos ,saltamos y realizamos otras activid
    12·1 answer
  • A car drives at a constant speed of 45km in 20mn. The speed of the car is..?​
    12·1 answer
  • If the applied force is 60 N and the lower mass is 1.0 kg, what is the tension in the string?(frictionless surface)
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!