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
quester [9]
3 years ago
10

A box with the mass of 15 kg is lifted to a shelf, how much force is needed?

Physics
1 answer:
viva [34]3 years ago
5 0
The object has a mass of 15 kilograms. Therefore, it weighs 147 newtons on Earth, where gravitational acceleration is 9.8 meters per second per second. To counteract gravity, the acting force needs to be at least 147 newtons, It has to move 3 meters upward. When multiplying force by distance, the product comes to 441 joules, where joules are the standard unit of work.
You might be interested in
An astronaut on a distant planet wants to determine its acceleration due to gravity. the astronaut throws a rock straight up wit
Tamiku [17]
Define
u = 16 m/s, the vertical launch velocity
g = acceleration due to gravity, measured positive downward
s = vertical distance traveled
t  = 21.2 s, total time of travel.

The vertical motion obeys the equation
s = ut - (1/2)gt²

When the rock is at ground level, s = 0.
Therefore
(16 m/s)(21.2 s) - 0.5*(g m/s²)*(21.2 s)² = 0
339.2 - 224.72g = 0
g = 1.5094 m/s²

Answer:
The acceleration due to gravity is 1.509 m/s² measured positive downward.


7 0
3 years ago
The amount of work done to bring an electron (q = −e) from right side of hydrogen nucleus to left side in the k shell is________
maksim [4K]

Answer:

d) 2Fr

Explanation:

We know that the work done in moving the charge from the right side to the left side in the k shell is W = ∫Fdr from r = +r to -r. F = force of attraction between nucleus and electron on k shell. F = qq'/4πε₀r² where q =charge on electron in k shell  -e and q' = charge on nucleus = +e. So, F = -e × +e/4πε₀r² = -e²/4πε₀r².

We now evaluate the integral from r = +r to -r

W = ∫Fdr

= ∫(-e²/4πε₀r²)dr

= -∫e²dr/4πε₀r²

= -e²/4πε₀∫dr/r²

= -e²/4πε₀ × -[1/r] from r = +r to -r

W = e²/4πε₀[1/-r - 1/+r] = e²/4πε₀[-2/r} = -2e²/4πε₀r.

Since F = -e²/4πε₀r², Fr = = -e²/4πε₀r² × r = = -e²/4πε₀r and 2Fr = -2e²/4πε₀r.

So W = -2e²/4πε₀r = 2Fr.

So, the amount of work done to bring an electron (q = −e) from right side of hydrogen nucleus to left side in the k shell is W = 2Fr

6 0
2 years ago
which way would 2 negatively charged balloons naturally move? what would that do to the amount of potential energy stored in the
zheka24 [161]

Answer:

gsg

Explanation:

5 0
3 years ago
A food packet is dropped from a helicopter during a flood-relief operation from a height of 750 meters. Assuming no drag (air fr
Leviafan [203]

1. Velocity at which the packet reaches the ground: 121.2 m/s

The motion of the packet is a uniformly accelerated motion, with constant acceleration a=g=9.8 m/s^2 directed downward, initial vertical position d=750 m, and initial vertical velocity v_0 = 0. We can use the following SUVAT equation to find the final velocity of the packet after travelling for d=750 m:

v_f^2 -v_i^2 =2ad

substituting, we find

v_f^2 = 2ad\\v_f = \sqrt{2ad}=\sqrt{2(9.8 m/s^2)(750 m)}=121.2 m/s

2. height at which the packet has half this velocity: 562.6 m

We need to find the heigth at which the packet has a velocity of

v_f=\frac{121.2 m/s}{2}=60.6 m/s

In order to do that, we use again the same SUVAT equation substituting v_f with this value, so that we find the new distance d that the packet travelled from the helicopter to reach this velocity:

v_f^2-v_i^2=2ad\\d=\frac{v_f^2}{2a}=\frac{(60.6 m/s)^2}{2(9.8 m/s^2)}=187.4 m

Which means that the heigth of the packet was

h=750 m-187.4 m=562.6 m

3 0
2 years ago
Estimate humanity’s current consumption of energy in one day (in Joule).
Alex73 [517]

Based on data from world energy consumption, the estimated humanity’s current consumption of energy in one day is above 208 million joules per day.

<h3>What is energy consumption?</h3>

Energy is the ability to do work. Therefore, energy consumption refers to the amount of energy used to do work.

Humans need energy for various purposes such as;

  • lighting
  • heating
  • operation of machines
  • feeding, etc.

Due to rapid growth on population as well as technology, the human energy consumption is on the increase.

In 2020, the world primary energy consumption was 71,4 GJ per person for a world population of about 7.7 billion people.

Therefore, the estimated humanity’s current consumption of energy in one day is above 208 million joules per day.

Learn more about energy at: brainly.com/question/6572692

6 0
2 years ago
Other questions:
  • "An empty cylindrical barrel is open at one end and rolls without slipping straight down a hill. The barrel has a mass of 19.0 k
    15·1 answer
  • What is energy efficiency
    12·1 answer
  • Which of the following statements is true?
    14·1 answer
  • While driving north at 21 m/s during a rainstorm you notice that the rain makes an angle of 36° with the vertical. while drivin
    6·1 answer
  • Micha ran 2 miles north in 20 minutes. She then turned back and ran 1 mile in 15 minutes. To cool down, she walked the rest of t
    7·1 answer
  • Which of these is an example of electromagnetic induction? A current passing through a resistor uses power IR2. A current throug
    11·1 answer
  • A large rock is weathered into tiny pieces which add up the weight of the original rock this demonstrates the conversion of ____
    6·1 answer
  • Electromagnetic waves vary in
    8·1 answer
  • The sum of the interior angles of a quadrilateral is _______. 180° 90° 270° 360°
    14·2 answers
  • The slotted arm OA rotates about a fixed axis through O. At the instant under consideration, θ = 36°, θ˙ = 36 deg/s, and θ¨ = 26
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!