Answer:
3N
Explanation:
The frictional force always acts directly opposite to the force of motion, that is it opposes motion. According to the Newton second law of motion:
Sum of horizontal forces = 0
Hence:
5N - 4(0.5) - F = 0
5 - 2 = F
F = 3N
How must a tennis serve start
Answer/Explanation:
When serving the primary serve, remain behind the benchmark between the middle imprint and the correct sideline. The ball is hit corner to corner into the administration box on the opposite side of the net, on the contrary side of the middle imprint from which the worker is serving.
which is not an insulator?
A wood
B plastic foam
C aluminum foil
D fiberglass
Answer:the answer is C aluminum foil
Explanation:
A 15-kg wagon is pulled to the right across a surface by a tension
of 100 newtons at an angle of 30 degrees above the horizontal.
A frictional force of 20 newtons to the left acts simultaneously.
What is the acceleration of the wagon?
Answer:
4.44 m/s^2
Explanation:
A 15-kg wagon is pulled to the right across a surface by a tension of 100 newtons at an angle of 30 degrees above the horizontal. A frictional force of 20 newtons to the left acts simultaneously.The acceleration of the wagon 4.44 m/s².
What is acceleration?The rate at which an item changes its velocity is known as acceleration, a vector quantity. If an object's velocity is changing, it is acceleration.
Given in the question a 15 kg wagon is pulled to the right across a surface by a tension of 100 newtons at an angle of 30 degrees above the horizontal. A frictional force of 20 newtons to the left acts simultaneously, then the acceleration is 4.44 m/s².
The acceleration of the wagon 4.44 m/s².
To learn more about acceleration refer to the link:
brainly.com/question/12550364
#SPJ2
What is the potential energy of a 2500 g object suspended 5 m above the earth's surface?
kilograms. convert mass to kilograms to solve this problem.
Answer:
Explanation:
Potential energy, which is the energy a body assumes at a position, can be calculated using the formula:
P.E = m × g × h
Where;
m = mass (kg)
g = acceleration due to gravity (10m/s²)
h = height (m)
Two displacement vectors have magnitudes of 5.0 m and 7.0 m, respectively. If these two vectors are added together, the magnitude of the sum
Answer:
8.6m
Explanation:
Step one:
given data
we are given two displacement vectors of magnitudes 5 and 7m
Let us assume they are in the same direction and they are acting perpendicular to each other.
Step two:
The magnitude of the vector sum is the resultant vector
which is found by
R^2=5^2+7^2
R^2= 25+49
R^2=74
R=√74
R=8.6m
helpp please
ASAP...
Answer:
I believe it to be option A
Explanation:
A volleyball experiences 494 Ns of impulse over a time period of 7 seconds. What was the magnitude of the force that acted on the volleyball during this time period?
Answer:
70.6N
Explanation:
Given parameters:
Impulse = 494Ns
Time = 7s
Unknown:
Force applied = ?
Solution:
To solve this problem, we use the formula of impulse;
Impulse = Force x time
Now insert the parameters and solve;
494 = Force x 7
Force = [tex]\frac{494}{7}[/tex]
Force = 70.6N
5) Choose the best revision of the following statement: "All the isotopes of a particular element decay radioactively by
emitting electrons."
A. All the isotopes of a particular element are stable and do not decay.
B. Some isotopes are stable and others are unstable. Unstable isotopes decay by emitting various subatomic
particles and radiation
C. Some isotopes are stable and others are unstable. Unstable isotopes decay by emitting protons or
electrons.
D. The statement is correct as it is currently written.
Answer:
B. some isotopes are stable and others are unstable. unstable isotopes decay by emitting various subatomic particles and radiation.
Explanation:
test gave me the answer so yeah :/ XD
6. A yo-yo with a mass of 0.5 kg is tied to a radius of 2 m and is spinning at 3 m/s. What
is the centripetal force acting on the yo-yo?
Given that,
Mass of yo-yo, m = 0.5 kg
Radius of the path, r = 2 m
Speed of the object, v = 3 m/s
To find,
The centripetal force acting on the yo-yo.
Solution,
The formula for the centripetal force is given as follows :
[tex]F=\dfrac{mv^2}{r}\\\\F=\dfrac{0.5\times (3)^2}{2}\\\\F=2.25\ N[/tex]
So, the magnitude of centripetal force acting on the y-yo is 2.25 N.
A boat moves through the water of a river at 8 m/s relative to the water, regardless of the boat's direction. If the water in theriver is flowing at 1.9 m/s, how long does it take the boat to makea round trip consisting of a 260 m displacement downstream followedby a 260 m
Answer:
68.88 m/s
Explanation:
downstream speed = 8+1.9=9.9 m/s
upstream speed = 8-1.9= 6.1 m/s
Therefore, total time taken would be 260/9.9+260/6.1 = 26.26+42.62 =
68.88 m/s
The intensity at a distance of 6 m from a source that is radiating equally in all directions is 6.0\times 10^{-10} W/m^2. What is the power emitted by the source
Answer:
P = 271 nW
Explanation:
If the source is radiating equally in all directions, it can be treated as a point source, so all points located at the same distance of the source, have the same intensity I, which is related to the power by the following expression:[tex]I = \frac{P}{A} =\frac{P}{4*\pi *r^{2} } (1)[/tex]
Solving for P, we get:[tex]P = I*4*\pi *r^{2} = 6.0e-10 W/m2 * 4 * \pi *(6m)^{2} =271 nW (2)[/tex]
A 2 kg block is sitting motionless on a ramp at 24° with the horizontal. What is the force of friction on the block that resists its motion?
Answer:
7.97 N
Explanation:
[tex]f = m g sin(\alpha) = 2 * 9.8 * sin(24) = 7.97 N[/tex]
A 1000 kg car crashed into a barrier. The car changed speed from 30 m/s to 20 m/s in 0.2 seconds. What force did the barrier apply to stop the car?
Answer:
Force = -50000 Newton
Explanation:
Given the following data;
Initial velocity, u = 30 m/s
Final velocity, v = 20 m/s
Time = 0.2secs
Mass = 1000 kg
First of all, we have to solve for its acceleration.
Acceleration = (v - u)/t
Substituting into the equation, we have
Acceleration = 20 - 30)/0.2
Acceleration = -10/0.2
Acceleration = -50m/s²
To find the force;
Force = mass * acceleration
Force = 1000 * (-50)
Force = -50000 Newton. The value of the force is negative because it stopped the motion of the car.
Therefore, the barrier applied a force of -5,0000 Newtons to stop the car.
Answer: -50000
Explanation:
If a small motor does 520 J of work to move a toy car 260 m, what force does the engine exert on the car?
Answer:
2 NExplanation:
The force engine exert on the car can be found by using the formula
[tex]f = \frac{w}{d} \\ [/tex]
w is the workdone
d is the distance
From the question we have
[tex]f = \frac{520}{260} = 2 \\ [/tex]
We have the final answer as
2 NHope this helps you
A water balloon is dropped off the top of a building and bursts when it hits
the ground 6 seconds later. What is the height of the building?
Answer:
The building is 176.4 meters high.
Explanation:
We use the formula for kinematics of an accelerated object (in this case acceleration of gravity):
Distance travelled = 1/2 g t^2
Distance travelled = 1/2 9.8 (6)^2 = 176.4 meters
A ball falls through the air at terminal velocity. Which of the following are forces that should be included in a free body
diagram? (select all that apply)
air resistance
force of motion
gravity
force of fall
Answer:
air resistance and gravity.
Explanation:
When the ball is falling down at terminal velocity, the velocity is constant.
This means that the net force acting on the ball will be zero (there is no acceleration)
In this situation, there are only two forces that can act on the ball.
The gravitational force, that pulls the ball down.
The air resistance which opposes to the movement of the ball and increases in magnitude as the velocity of the ball increases.
Then there is a point where the velocity of the ball is such that the air resistance is equal in magnitude to the acceleration, and then the net force becomes zero.
Then the two forces that need to be included in this diagram are the air resistance and gravity.
3. Missy Diwater, the former platform diver for the Ringling Brother's Circus, had a kinetic energy of 12,000 ) just prior to hitting the bucket of water. If Missy's mass is 40 kg, then what is her speed?
Answer:
v = 24.49[m/s]
Explanation:
We must remember that kinetic energy can be calculated by means of a mathematical expression, which relates kinetic energy to mass and velocity
[tex]E_{kin}=\frac{1}{2}*m*v^{2} \\[/tex]
where:
Ekin = kinetic energy = 12000 [J]
m = mass = 40 [kg]
v = velocity [m/s]
[tex]12000=\frac{1}{2} *40*v^{2}\\24000=40*v^{2}\\600=v^{2}\\v=\sqrt{600}\\v=24.49[m/s][/tex]
Imagine you were lifting very heavy jugs to the top of a house. You can either use the stairs on the left or push them up the inclined plane on the right. Which option is easier
Answer:
Use the stairs
Explanation:
This is easier because if you go on the stairs you can rest if you get tired but if you go on the inclined plane then the weight of the jugs will make you slower than you already are and you may end up going back down instead of up where you wanna go.
Help Help!!
Alcohol ___ the central nervous system and the peripheral nervous system.
A. sedates
B. stimulates
C. bypasses
Answer:
I think it is the answer A
Explanation:
Alcohol won't stimulate the central nervous system and the peripheral nervous system because the fact that the brain and the nervous system are affected can lead to many consequences: disorders of vision, hearing, motor coordination ...
Alcohol will therefore have a damaging effect, it will therefore sedate the nervous system.
Answer:A
Explanation:sedates
1. Calculate the momentum of a 1.0 kg object moving with a velocity of +20 m/s.
2. What is the velocity of an object that has a momentum of -30 kg m/s and a mass of 3.0 kg?
3. Two objects have equal momentum but one has four times the mass of the other. What is the relationship between
their velocities?
4. Which answer below shows the correct units for momentum?
A. kg m/s
B. kg m/s?
C. kg m/s
D. kg s/m
5. Two bowling balls each have a mass of 4.0 kg
The red Bar is moving east 2.0 m/s. The blue ball is moving west at 1.0 m/s. Calculate the total momentum of the system.
Answer:
1)1*20=20
2)-30/3=- -10
3)velocity of the object 1=v1=4*V2
4) kg m/ s
5) momentum of the system= 12 kg m/ s
A dynamite blast blows a heavy rock straight up from the ground with a launch velocity of 160ft/sec. a) Write the height function.
Answer:
y = 160t - 16t²
Explanation:
Using y = ut -1/2gt² where y = height of heavy rock above the ground, u = initial launch velocity of rock = 160 ft/s, g = acceleration due to gravity = 32 ft/s² and t = time.
So, substituting the values of the variables into y, we have
y = (160 ft/s)t -1/2 × 32 ft/s² × t²
y = (160 ft/s)t - (16 ft/s²)t²
y = 160t - 16t²
So, the height function is y = 160t - 16t²
horizontal range = 200m, maximum height= 25m find the angle of projection.
Answer:
θ = 26.6°
Explanation:
Formula for maximum height is;
h = u²sin²θ/2g
We are told maximum height is 25 m, thus;
u²sin²θ/2g = 25 - - - - (eq 1)
Formula for horizontal range is;
R = u²sin2θ/g
In Mathematics, sin2θ = 2sinθcosθ
So; R = 2u²sinθcosθ/g
R = 2u²sinθcosθ/g
We are given Horizontal range = 200 m.
Thus;
2u²sinθcosθ/g = 200 - - - - (eq 2)
Divide eq 1 by eq 2 to get;
200/25 = 4cosθ/sinθ
8 = 4cosθ/sinθ
4/8 = sinθ/cosθ
0.5 = tan θ
θ = tan^(-1) 0.5
θ = 26.6°
A construction laborer holds a 20 kg sheet of wallboard 3 m above the floor for 4 seconds. During these 4 seconds how much power was expended on the wallboard
Answer:
zero
Explanation:
no distance has moved while holding the sheet...so no distance means no workdone..no workdone means no power...
is this right? plzz anwser soon
Answer:
yes
Explanation:
Answer:
y e p
Explanation:
A force can change an object's direction and cause friction
True or False
Answer:
This is very true
Explanation:
The force from impact can easily change it to expanse in a different direction.
I hope this helped you very much :)
A metallic ring of mass 1 kg has moment of inertia 1 kg m² when rotating about one of its diameters. It is molten and
remoulded into a thin uniform disc of the same radius. How much will its moment of inertia be, when rotated about its own
axis.
Answer:
The moment of inertia of disc about own axis is 1 kg-m².
Explanation:
Given that,
Mass of ring m= 1 kg
Moment of inertia of ring at diameter [tex](I_{r})_{d}=1\ kg\ m^{2}[/tex]
The radius of metallic ring and uniform disc both are equal.
So, [tex]R_{r}=R_{d}[/tex]
We need to calculate the value of radius of ring and disc
Using theorem of perpendicular axes
[tex](I_{r})_{c}=2\times (I_{r})_{d}[/tex]
Put the value into the formula
[tex](I_{r})_{c}=2\times1[/tex]
[tex](I_{r})_{c}=2\ kg\ m^2[/tex]
Put the value of moment of inertia
[tex]MR_{r}^2=2[/tex]
[tex]R_{r}^2=\dfrac{2}{M}[/tex]
Put the value of M
[tex]R_{r}^2=\dfrac{2}{1}[/tex]
So, [tex]R_{r}^2=R_{d}^2=2\ m[/tex]
We need to calculate the moment of inertia of disc about own axis
Using formula of moment of inertia
[tex]I_{d}=\dfrac{1}{2}MR_{d}^2[/tex]
Put the value into the formula
[tex]I_{d}=\dfrac{1}{2}\times1\times2[/tex]
[tex]I_{d}=1\ kg\ m^2[/tex]
Hence, The moment of inertia of disc about own axis is 1 kg-m².
What is the current in a 160V circuit if the resistance is 200?
A car with a mass of 2,000 kg travels at 20 m/s. Which one has the greatest impulse?
Answer:2000kg
Explanation:
Convert it
A projectile is fired with a velocity of 8 m/s at an angle of 65º. What is the
vertical component of the velocity?
A. 6.5 m/s
B. 3.4 m/s
C. 10.2 m/s
D. 7.2 m/s
Answer:
i think its D
Explanation:
Which describes velocity?
Answer:
Velocity is the rate at which the position changes. The average velocity is the displacement or position change per time ratio.
Explanation:
Answer:
The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity is equivalent to a specification of an object's speed and direction of motion (e.g. 60 km/h to the north).
Other units: mph, ft/s
In SI base units: m/s
Explanation:
i dont know if this helps.