Answer:
atomic weight 20.180
protons 10
neutrons 2,8
Explanation:
A 20 kg mass is hanging on one side of a pulley and a 5 kg mass is hanging on the other. Determine the acceleration of each mass.
Answer:
i believe it's 7
Explanation:
Particles in which state of matter are the most likely to interact with each other to cause a chemical reaction?
HELP ASAP TIMER
Your younger brother gets a new toy car as a present. He winds up the toy, puts it on the ground and watches it accelerate for 5 seconds. You can explain how to find the net force acting on the toy car for the 5 seconds while accelerating by the following:
a
Use a meterstick and stopwatch to measure the distance the car travels for the 5s.
b
Use a balance to determine the mass of the car. Use a motion sensor to measure the speed of the car at a time of 0s and at time of 5s .
c
Use a balance to determine the mass of the car. Use a meterstick to measure the distance the car travels for the 5s .
d
Use a motion sensor to measure the speed of the car at a time of 0s and a time of 5s . Use a meterstick to determine the distance the car travels for 5s .
Answer:
b Use a balance to determine the mass of the car. Use a motion sensor to measure the speed of the car at a time of 0s and at time of 5s .
Explanation:
The right way to measure the net force on the car is take the measurement of its mass then find the speed of the car within the time 0s to 5s.
This is because the net force acting on car is given as;
Force = mass x acceleration
By using the balance, the mass is determine
Acceleration is the rate of change of velocity with time.
Acceleration = [tex]\frac{v - u}{t}[/tex]
v is the final velocity
u is the initial velocity
t is the time taken
Now,
Force = mass x [tex]\frac{v - u}{t}[/tex]
How does the electric force between two charged particles change if the
distance between them is reduced by a factor of 2?
A. It is reduced by a factor of 2.
B. It is increased by a factor of 4.
C. It is increased by a factor of 2.
D. It is reduced by a factor of 4.
Answer:
increased by a factor of 4
Explanation:
What is the density of an object with a mass of 20 grams and a volume of 5 cm?
Answer:
4
Explanation:
Divide mass(m) by volume(v), you get density(D)
m/v=D
20/5=4
please help me pwease
Answer:
Iron
Explanation: It is by mass the most common element on Earth, right in front of oxygen, forming much of Earth's outer and inner core.
Name the following ionic compounds: BeCl2
Answer:
Beryllium chloride
Explanation:
I hope this helps!
Can I get branliest?!
These the flow of electrons (the current) and where some of the electrons' energy gets converted into heat. (Lessons 5.01-5.03) electric currents Insulators Resistors Conductors
Answer: The answer is resistors
Explanation: I just took the unit test and it was correct
A fireboat is to fight fires at coastal areas by drawing seawater with a density of 1030 kg/m3 through a 10-cm-diameter pipe at a rate of 0.04 m3/s and discharging it through a hose nozzle with an exit diameter of 5 cm. The total irreversible head loss of the system is 3 m, and the position of the nozzle is 3 m above sea level. For a pump efficiency of 70 percent, determine the required shaft power input to the pump and the water discharge velocity.
Answer:
50.93 m/s
199.5 kW
Explanation:
From the question, the nozzle exit diameter = 5 cm, Radius= diameter/2= 5cm/2= 2.5cm. we can convert it to metre for unit consistency= (2.5×0.01)=
0.025m
We can calculate the The cross sectional area of the nozzle as
A= πr^2
A= π ×0.025^2
= 1.9635 ×10^- ³ m²
From the question, the water is moving through the pipe at a rate of 0.1 m /s , then for the water to move through it at a seconds, it must move at
(0.1 / 1.9635 ×10^- ³ m²)
= 50.93 m/s
During the Operation of the pump, the Dynamic energy of the water= potential energy provided there is no loss during the Operation
mgh = 1/2mv²
We can make "h" subject of the formula, which is the height of required head of water
h = (1/2mv²)/mg
h= v² / 2g
h = 50.93² / (2 ×9.81)
h = 132.21m
From the question;
The total irreversible head loss of the system = 3 m,
the given position of nozzle = 3 m
the total head the pump needed=(The total irreversible head loss of the system + the position of the nozzle + required head of water )
=(3 + 3 + 132.21m)
=138.21m
mass of water pumped in a seconds can be calculated since we know that mass is a product of volume and density
Volume= 0.1m³
Density of sea water=1030 kg/m
(0.1 m^3× 1030)
= 103kg
We can calculate the Potential enegry, which is = mgh
= (103 ×9.81 × 138.21)
= 139651.5 Watts
= 139.65kW
To determine required shaft power input to the pump and the water discharge velocity
Energy= efficiency × power
But we are given efficiency of 70 percent, then
139651.5 Watts = 0.7P
=199502.18 Watts
P=199.5 kW
Therefore, the required shaft power input to the pump and the water discharge velocity is 199.5 kW
A gun fires a bullet horizontally with a velocity of 90 m/s from a tower. Neglecting air resistance, how far will the bullet travel horizontally in 4 seconds?
Answer:
The distance covered along the horizontal axis is [tex]s = 360 \ m[/tex]
The distance covered along the vertical axis is [tex]h = 78.4 \ m[/tex]
Explanation:
From the question we are told that
The horizontal velocity is [tex]u_x = 90 \ m/s[/tex]
The time considered is [tex]t = 4 \ s[/tex]
Generally the distance which the bullet will cover in the horizontal direction for the given time is mathematically represented as
[tex]s = u_xt + \frac{1}{2}* at^2[/tex]
Here a is the acceleration along the horizontal direction and the value is [tex]a = 0 \ m/s^2[/tex]
So
[tex]s = 90 * 4 + \frac{1}{2}* * 0 * 4^2[/tex]
=> [tex]s = 360 \ m[/tex]
Generally the distance which the bullet will cover in the vertical direction for the given time is mathematically represented as
[tex]h= u_y t + \frac{1}{2}* gt^2[/tex]
Here [tex]u_y[/tex] is the initial velocity of the bullet along the vertical axis and the value is [tex]u_y = 0 \ m/s[/tex]
[tex]h = 0 * 4 + \frac{1}{2}* 9.8 *4^2[/tex]
=> [tex]h = 78.4 \ m[/tex]
A 35kg cannonball sits at rest on a flat level surface. What is the normal force exerted on the cannon ball. Use -9.8 m/s2 for acceleration due to gravity.
A. -343N
B. 44.8N
C. 25.2N
D. 343N
Answer:
a) N = 343 [N]
Explanation:
We must remember Newton's third law, which tells us that the force acting on a body is equal to the normal reaction force of equal magnitude but acting in the opposite direction.
[tex]N=m*g[/tex]
where:
m = mass = 35 [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]N = 35*9.8\\N= 343 [N][/tex]
Light that enters your eye strikes cells in the back of your eye
true
False
Answer: True
Explanation: Light enters your eye through the lens which then hits the retina which is located in the back of your eye.
Question 1 of 25
A bookcase has a mass of 37 kg. What is the weight of the bookcase?
Help please
answers
81.6 pounds rounded or just 81.571 if it needs to be exact
41. What effects the efficiency of a pulley?
a. the type of rope or cable
b. the way the wheel turns
c. the length of the rope
d. how big the wheel is
e. only a and be
f. all of the above
Answer:
e. only a and b
D. Ampere
A screw of length 5 cm enters totally into a wooden block after 25 turns. What is the pitch of the
screw?
A. 0.1 cm
B. 0.2 cm
C. 0.4 cm
D. 0.5 cm
Answer:
0.5
Explanation:
u must simplyfiy
What do we know about the relative strength of the electric field around each object?
Answer:
A charged object in an electric field experiences a force due to the field. The electric field strength, E, at a point in the field is defined as the force per unit charge on a positive test charge placed at that point.
Explanation:
12. How many grams of beryllium are needed to produce 36.0 g of hydrogen? (Assume an excess of water.)
Be(s) + 2H, O() → Be(OH)2 (aq) +H,(g)
a
4.00 g
b. 36.0 g
c. 162 g
d 324 g
Answer:
Answer is: 162 g of beryllium.
Chemical reaction: Be + 2H₂O → Be(OH)₂ + H₂.
m(H₂) = 36,0 g.
m(Be) = ?
n(H₂) = m(H₂) ÷ M(H₂)
n(H₂) = 36,0 g ÷ 2 g/mol = 18 mol.
from reaction: n(Be) : n(H₂) = 1 : 1.
n(Be) = n(H₂) = 18 mol.
m(Be) = n(Be) · M(Be).
n(Be) = 18 mol · 9 g/mol = 162 g.
Answer:
Answer is: 162 g of beryllium.
Chemical reaction: Be + 2H₂O → Be(OH)₂ + H₂.
m(H₂) = 36,0 g.
m(Be) = ?
n(H₂) = m(H₂) ÷ M(H₂)
n(H₂) = 36,0 g ÷ 2 g/mol = 18 mol.
from reaction: n(Be) : n(H₂) = 1 : 1.
n(Be) = n(H₂) = 18 mol.
m(Be) = n(Be) · M(Be).
n(Be) = 18 mol · 9 g/mol = 162 g.
a 50.0kg skydiver experience a 740newton air resistance force determine her acceleration please help asap
Answer:
a = - 5 [m/s²].
Explanation:
To solve this problem we must use Newton's second law, which tells us that the sum of forces on a body is equal to the product of mass by acceleration.
∑F = m*a
where:
F = resultant force [N] (units of Newtons)
m = mass = 50 [kg]
a = acceleration = 9.81 [m/s²]
For this particular problem, the only forces acting are the force of gravity acting down with negative sign, while the force of air opposes the fall, in this way it is positive.
[tex]f_{air}-F_{grav}=-m*a[/tex]
As the movement is pointing down the acceleration will be taken as negative.
[tex]740-(50*9.81)=-50*a\\740-490.5 = -50*a\\249.5 = -50*a\\a = - 5 [m/s^{2} ][/tex]
We should note that in this case, the acceleration has a negative sign, this means that the force of the air makes the skydiver move upwards
How to find acceleration?
Answer:
a=(v-u)/t is how you find acceleration.
When you walk across the ground and push on it with your feet...
Group of answer choices
The ground pushes back more strongly than your feet
The ground pushes back on your feet with equal force
There is no effect on the ground
The ground pushes back less strongly than your feet
Answer:
The ground pushes back on your feet with equal force
Explanation:
When you walk across the ground and push on it with your feet, the ground pushes back on your feet with an equal and opposite force.
This interpretation and knowledge is gotten from Newton's third law of motion.
It states that "action and reaction force are equal and opposite in nature".
The force applied to a body responds with an opposite force in the other direction. Therefore, the reaction force is of equal magnitude but directed in another direction.Answer:
the answer is the second one: the ground pushes back on your feet with equal force
Explanation:
You use a lever to lift a heavy tree branch. You apply a force of 30 N and the
lever lifts the branch with a force of 120 N. What is the mechanical advantage
of the lever?
A. 4
B. 0.25
C. 2
D. 90
Answer:
D 90 subtract it
Explanation:
Please help ASAP, studying for finals.
A racecar rounds a curve on the track at a constant speed of 180 mph. Is the car accelerating?
1)No, its mass is constant.
2)Yes, its mass is constant.
3) No, its speed is constant.
4)Yes, its speed is constant.
Answer:
3)No, it's speed is constant.
What do you think menas to be Physically fit.
Answer:
consistently working out and eating healthy i guess
Explanation:
Answer:
To have a strong body (not only visible muscles). Physically fit is to eat well also. Eat healthy more! Your body might not be packin, but it sure is strong!
Explanation:
Hope this Helps!
Have a great day!
:)
When a person strikes and lights a match, potential energy in the match is transformed into which types of energy?
electrical and thermal
thermal and radiant
radiant and nuclear
nuclear and kinetic
hurry brainliest ill give 49 points
Answer:
Radiant and thermal
Explanation:
Electrical and thermal don't make sense because you are not using electricity to light the match. Radiant and nuclear is not right because you are not using nuclear energy to light the match. Nuclear and kinetic isn't right because you are using kinetic and you are not using nuclear energy.
Answer:
answer is B. thermal and radiant
Explanation:
just got it right on edge
This image shows flashlight beams reflecting off a mirror from
different angles. Based on the angles of reflection, choose all pairs of
light rays that correctly match incoming light beams with their
reflected light beams,
Question 2. Based on the image and the angles of reflection shown witch statement is true.
A) When a light ray strikes a mirror, it randomly scattered.
B) light is absorbed by mirrors and reflected directly upwards.
C) light travels in a straight line until lit strikes an object
D) light is reflected back to its source when it strikes an object
Hey I'm working on this test right now, did you ever get the answers?
Help me pretty please with a cherry on top!!
Answer:
A. im not for sure hope it helps
Explanation:
The water cycle is an example of a * 2 points A) matter being cycled in a closed system B) an open system because water can come in from outside Earth's closed system C) energy being cycled in an opened system D) matter being cycled in an open system
A supply plane drops a package to the ground for stranded campers below. After falling for 8.14 seconds, the package will have a downward velocity of 80.79 m/s. How high was the plane when it dropped the package?
Answer:
333 m
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 0 m/s.
Time (t) = 8.14 s.
Final velocity (v) = 80.79 m/s.
Acceleration due to gravity (g) = 9.8 m/s²
Height (h) =?
v² = u² + 2gh
80.79² = 0 + (2 × 9.8 × h)
6527.0241 = 0 + 19.6h
6527.0241 = 19.6h
Divide both side by 19.6
h = 6527.0241 / 19.6
h = 333 m
Thus, the plane was at a height of 333 m when the package was dropped.
What two things does force depend on
Answer:
When dealing with the force of gravity between two objects, there are only two things that are important – mass, and distance or (acceleration)
Explanation:
a car travels 200km in 3.0 hours. Determine the average velocity of the car
Answer:
66.67 km/hrExplanation:
The average velocity of the car can be found by using the formula
[tex]a = \frac{d}{t } \\ [/tex]
d is the distance
t is the time taken
From the question we have
[tex]a = \frac{200}{3} \\ = 66.66666...[/tex]
We have the final answer as
66.67 km/hrHope this helps you