Answer:
a. i His weight and the normal force on him due to the ground
ii The weight and the normal force are balance
b. There are four forces acting on him while he is walking. These are the backward push due to his leg on the ground and the frictional force between his feet in the horizontal direction and, his weight and normal force on his feet in the vertical direction.
Explanation:
a. i Describe the forces that are acting on a person who is standing still on a sidewalk
His weight and the normal force on him due to the ground act on him while the person is standing on the sidewalk
ii. identify whether the forces are balanced or unbalanced.
The weight and the normal force are balance because, the person does not move in the vertical or horizontal direction.
b. Describe how the forces would change if the person started walking.
When the person starts walking, the backward push due to his leg on the ground and the frictional force between his feet and the ground now acts on him in the horizontal direction. The frictional force acts in the forward direction and tends to move him forward. His weight and normal force on his feet still act vertically and are both balanced since he does not move in the vertical direction.
So, there are four forces acting on him while he is walking. These are the backward push due to his leg on the ground and the frictional force between his feet in the horizontal direction and, his weight and normal force on his feet in the vertical direction.
When serving you start on the right and must hit to which designated area?
- right side you are looking at
- left side you are looking
- any place over the net
(pickle ball)
you can serve to anyplace over the net
If you are in a car that stops suddenly, what does your body continue to do?
Answer:
If the passengers were not wearing their seat belts:, then the passengers in motion would continue in motion. Assuming a negligible amount of friction between the passengers and the seats, the passengers would likely be propelled from the car and be hurled into the air. Once they leave the car, the passengers becomes projectiles and continue in projectile-like motion.
If they were: Any passengers in the car will also be decelerated to rest if they are strapped to the car by seat belts. Being strapped tightly to the car, the passengers share the same state of motion as the car. As the car accelerates, the passengers accelerate with it; as the car decelerates, the passengers decelerate with it; and as the car maintains a constant speed, the passengers maintain a constant speed as well.
I got this from https://www.physicsclassroom.com
A book is resting on the floor. It has 25 J of energy. A student lifts the book and places it on the top shelf of a bookshelf. The student uses 200 J of energy to lift the book onto the shelf. How much energy does the book have at the top of the shelf?
A.Exactly 25 J
B. About 225 J
C. At least250 J
D.Negative 175 J PLSS QUICK (3 minutes at most) ILL GIVE 70 POINTS AND BRAINLIEST (FOR CORRECT ANSWER)
Answer and Explanation:
A. Exactly 25 J.
This is because the 25 J of energy that is holding down the book will always be the same, unless another force is being applied to hit to either make it heaver for a combined force of J energy, or something is lifting it, which will subtract the force of J of energy whilst moving.
#teamtrees #PAW (Plant And Water)
What is the kinetic energy of a 78kg object moving at a velocity of 2.5m/s
Answer:
[tex]\boxed {\boxed {\sf 243.75 \ J }}[/tex]
Explanation:
Kinetic energy is energy an object has due to motion. The formula is:
[tex]KE=\frac {1}{2}mv^2[/tex]
The mass of the object is 78 kilograms and the velocity is 2.5 meters per second.
[tex]m= 78 \ kg \\v= 2.5 \ m/s[/tex]
Substitute the values into the formula.
[tex]KE= \frac {1}{2} (78 \ kg)*(2.5 \ m/s)^2[/tex]
Solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction. Solve the exponent first.
(2.5 m/s)²= 2.5 m/s * 2.5 m/s = 6.25 m²/s²[tex]KE= \frac {1}{2}(78 \ kg)*6.25 \ m^2/s^2[/tex]
Multiply all three numbers together.
[tex]KE=39 \ kg * 6.25 \ m^2/s^2\\[/tex]
[tex]KE=243.75 \ kg*m^2/s^2[/tex]
1 kilogram meter squared per second squared is equal to 1 Joule. So, our answer of 243.75 kg *m²/s² is equal to 243.75 Joules.
[tex]KE=243.75 \ J[/tex]
The object has 243.75 Joules of kinetic energy.
A block of density 8.9g/cm³ measures 5cm by 2cm, Given that the force of gravity is 10N/kg. Determine the maximum pressure
Answer:
Maximum pressure = 4450 N/m²
Explanation:
We'll begin by calculating the volume of the block. This can be obtained as follow:
Volume (V) = 5 cm × 3 cm × 2 cm
V = 30 cm³
Next, we shall determine the mass of the block. This can be obtained as follow:
Density = 8.9 g/cm³
Volume = 30 cm³
Mass =?
Density = mass /volume
8.9 = mass / 30
Cross multiply
Mass = 8.9 × 30
Mass = 267 g
Next, we shall covert 267 g to Kg.
1000 g = 1 Kg
Therefore,
267 g = 267 g × 1 Kg / 1000
267 g = 0.267 Kg
Thus, the mass of the block is 0.267 Kg
Next, we shall determine the force.
Force of gravity (g) = 10 N/Kg
Mass (m) = 0.267 Kg
Force (F) =?
F = mg
F = 0.267 × 20
F = 2.67 N
Next, we shall determine the minimum area since we are trying to obtain the maximum pressure. This can be obtained as follow:
Minimum area = 3 cm × 2 cm
Covert each measurement to metre (m) by dividing each measurement by 100
Minimum area = 0.03 m × 0.02 m
Minimum area = 0.0006 m²
Finally, we shall determine the maximum pressure. This can be obtained as follow:
Force (F) = 2.67 N
Minimum area = 0.0006 m²
Maximum pressure =?
Maximum pressure = Force /minimum area
Maximum pressure = 2.67 / 0.0006
Maximum pressure = 4450 N/m²
A book is placed on a table and a bike moves on a road.
Which statement is correct?
Both the book and the bike have kinetic energy.
Both the book and the bike have potential energy.
The book has potential energy and the bike has kinetic energy.
The book has kinetic energy and the bike has potential energy.
The book has potential energy and the bike has kinetic.
kinetic energy is energy possessed when a object is in motion. The bike is moving. Therefore, it has kinetic energy. The book isn't moving. Hopefully that helped
help meeeeeeeeeeee
what is the rheostat and what its ruleeee??
Answer:
Rheostat, adjustable resistor used in applications that require the adjustment of current or the varying of resistance in an electric circuit. The rheostat can adjust generator characteristics, dim lights, and start or control the speed of motors.
Explanation:
Water heating over a stove
ahh yes
Y. E. S. W A. T. E. R. A. N. D. S T. ON. V. E
A 8.0-g bullet with an initial velocity of 115.0 m/s lodges in a block of wood and comes to rest at a
distance of 4.0 cm. Assume the bullet undergoes a constant negative acceleration; it slows at a
constant rate.
a. How much time does it take for the bullet to stop?
b. What is the impulse on the woodblock?
c. What is the average force experienced by the block?
These 2 processes cause watersheds to change.
Answer:
Change is an integral component of the watershed. The wide variations in river and stream flow regularly change shorelines, stream channels and stream corridors. Upland areas of watersheds also undergo changes due to ecological succession, disease, competition, human activity and other factors.
Explanation:
Please ans fast I will mark brainliest
For sure
use the following terms in the same sentence magnet magnetic force and magnetic pole
Answer:
The electrically charged gas particles are affected by magnetic forces.
For the past eleven years, the Sun's north geographic pole has also been home to its north magnetic pole
Explanation:
A dog sits on a flat surface. If the dog has a mass of 13 kg, what is the normal force acting on it?
85 N
13 N
127 N
41 N
Answer:
127
Explanation:
f(n)=mg
(13)*(9.81)
127.4N
What is happening when an oxygen molecule is formed from two separate oxygen atoms?
Two from each oxygen atom. For examples of covalent bonding are water (H2O), and carbon dioxide (CO2). Covalent compounds are mostly gases or liquids with low melting points.
Why should Mike repeat this investigation?
Mike needs to make sure that all the skateboards are not affected by friction.
Mike needs to have more than one set of numbers to make an accurate graph
The investigation needs multiple trials to determine which board is the control.
The investigation needs to be repeated several times to have the most accurate data.
Answer:
D
Explanation:
PLEASE help its timed..
Which statement describes how a machine can help make work easier?
A)It can put out more force than the input force by decreasing the distance over which force is applied.
B) It can increase the amount of work performed if the output force is in the same direction as the input force.
C) It can apply a greater output force over a greater distance compared to the input force and distance.
D) It can increase the distance over which output force acts by applying less output force than input force.
Answer:
D
Explanation:
by increasing the distance through which force is applied, by changing the direction of force applied or by multiplying force of speed of the energy applied
1.) Cameron loads a wheelbarrow full of dirt. She then holds up both handles and begins to push it across her yard. The push Cameron uses to move the wheelbarrow is an example of
trajectory
motion
dynamics
force
2.) Jeremy is pushing his two children on a set of swings. He gives his daughter a push and she swings about three feet high. Jeremy gives his son the same push, but he only swings about two feet high. What could account for the difference in how high the kids got?
Jeremy's daughter has more mass, so it takes less force to get her into the air.
Jeremy's son has more mass, so it would take more force to reach the same height as his daughter.
Jeremy's son has less mass, so it would take more force to reach the same height as his daughter.
Jeremy's daughter has more mass, so she accelerates faster than his son.
Answer:
C (Force)
Explanation:
Cmon we should all know dis
Answer:
force and Jeremy's son has more mass
Explanation:
pushing requires force and the son moves less
A king orders a gold crown having a mass of 0.5 kg. When it arrives from the metalsmith, the volume of the crown is found to be 185 cm3. Is the crown made of solid gold?
Answer:
The crown is not made of solid gold.
Explanation:
Density ρ = M/V. M and V are given.
The density of the crown is (0.5 kg)/(185 cm3) * (106 cm3)/(1 m3) = 2.7*103 kg/m3.
What could be the average human density? Justify?
Answer:
985 kg/m3
Explanation:
The average density of the human body is 985 kg/m3 k g / m 3 , and the typical density of seawater is about 1020 kg/m3 k g / m 3 .
Explanation:
the worldwide human population density is around 7,500,000,000 ÷ 510,000,000 = 14.7 per km2 (38 per sq. mi.). If only the Earth's land area of 150,000,000 km2 (58,000,000 sq. mi.) is taken into account, then human population density is 50 per km2 (129 per sq.
This is graded help hurry pls
The picture below shows a wheelbarrow. Using a wheelbarrow can make it easier to lift a heavy object by
A. changing the direction of the input force.
B. reducing the amount of input force needed to lift the object.
C. decreasing the distance over which the input force is applied.
D. reducing the weight of the object.
Answer:
B IS CORRECT
Explanation:
4. An automobile gasoline engine is able to do 225 J of useful work with each stroke of its
pistons. If the engine has an efficiency of 29%, what is the amount of work that must be done on
the pistons in the engine?
[tex]\mathfrak{\huge{\orange{\underline{\underline{AnSwEr:-}}}}}[/tex]
Actually Welcome to the concept of Efficiency.
We know that, efficiency is given as,
E (eta) = Output work / Input Work
hence, here, E = 29% and Output work = 225
hence, 29% = 29/100 in real..
hence, the work done on piston is given as,
29/100 = 225/I
therefore, I = 225*100/29 ==> I = 22500/29 ==> I = 775.8 joules
hence, the work done on the pistons is 775 J
PLZZ IF ANYONE KNOWS SCIENCE HELP ME PLZ I this is so confusing :(
ill liderally make a question with 50 and a brainliest since you helped me ;-;
Answer:
i think it would be either b or c because....
Explanation:
"The desert biome is best adapted for aloe because aloe plant usuallly grows in open area under sunlight exposure where the intensity of sunlight is very high. Its grows in very rocky, dry and open areas."
Give me two examples of a pushing force and two examples of a pulling force:
Answer:
A pushing force example could be a button, like on a keyboard.
Another example would be a piston.
An example of a pulling force could be a lever.
Another example could be rope.
Hope this helps! c:
The elements in which section of the periodic table are the most stable and rarely react with other elements?
А metals
B metalloids
С noble gases
D nonmetals
Which color has the lowest frequency?
give the relation of speed of sound with the density and temperature
Answer:
The greater the density of a medium, the slower the speed of sound. This observation is analogous to the fact that the frequency of a simple harmonic motion is inversely proportional to m, the mass of the oscillating object.
Air molecules have more energy at higher temperatures, which means they vibrate faster. This allows the sound waves to also travel faster because they are propelled by collisions between the molecules
Un cuerpo lleva una velocidad de 122k por hora y de golpe frena reduciendo su velocidad a 50km por hora en un instante de tiempo de 4,5 segundos y la fuerza de frenado es de 1200n, ¿cual será su masa?
Answer:
La masa del objeto es 270.027 kilogramos.
Explanation:
Asumamos que el cuerpo decelera a tasa constante, entonces podemos calcularlo por medio de la siguiente ecuación cinemática:
[tex]a = \frac{v-v_{o}}{t}[/tex] (1)
Donde:
[tex]v_{o}[/tex] - Velocidad inicial, en metros por segundo.
[tex]v[/tex] - Velocidad final, en metros por segundo.
[tex]t[/tex] - Tiempo, en segundos.
[tex]a[/tex] - Deceleración, en metros per segundo al cuadrado.
Si sabemos que [tex]v_{o} = 33.889\,\frac{m}{s}[/tex], [tex]v = 13.889\,\frac{m}{s}[/tex] y [tex]t = 4.5\,s[/tex], entonces la deceleración experimentada por el cuerpo es:
[tex]a = \frac{v-v_{o}}{t}[/tex]
[tex]a = -4.444\,\frac{m}{s^{2}}[/tex]
Por las Leyes de Newton, tenemos que la masa del cuerpo se calcula a partir de la siguiente expresión:
[tex]m = \frac{F}{a}[/tex] (2)
Donde:
[tex]m[/tex] - Masa, en kilogramos.
[tex]F[/tex] - Fuerza de frenado, en newtons.
Si sabemos que [tex]F = -1200\,N[/tex] y [tex]a = -4.444\,\frac{m}{s^{2}}[/tex], entonces la masa del cuerpo es:
[tex]m = \frac{F}{a}[/tex]
[tex]m = 270.027\,kg[/tex]
La masa del objeto es 270.027 kilogramos.
If the vehiche has a speed of 24.0 m/s at point a what is the force of the track on the vehicle at this point?
Question:
A roller-coaster vehicle has a mass of 500 kg when fully loaded with passengers. If the vehicle has a speed of 20.0 m/s at point A, what is the force exerted by the track on the vehicle at this point?
See attachment
Answer:
33700 Newton
Explanation:
Given
[tex]m = 500kg\\v = 24.0m/s\\r=10m[/tex]
First, we determine the forces acting on mass m.
They are: the force exerted by the track (Fn) and the weight of the vehicle (W)
So, the net force is:
[tex]F_{net} = F_n - W[/tex]
[tex]W=mg[/tex]
So:
[tex]F_{net} = F_n - mg[/tex]
Make Fn the subject
[tex]F_n = F_{net} + mg[/tex]
Fnet is calculated as:
[tex]F_{net} = F_c = \frac{mv^2}{r}[/tex] --- i.e. the centripetal force
So:
[tex]F_n = F_{net} + mg[/tex]
[tex]F_n = \frac{mv^2}{r} + mg[/tex]
[tex]F_n = \frac{500 * 24^2}{10} + 500 * 9.8[/tex]
[tex]F_n = 28800 + 4900[/tex]
[tex]F_n = 33700N[/tex]
Which choice Not a direct risk of eating a diet too high in sugar? 1 diabetes 2 weight gain 3 tooth decay 4 weight loss
Answer:
4 weight loss
Explanation:
