Acceleration = (change in speed) / (time for the change)
Change in speed = (speed after the change) - (speed before the change)
Change in speed = (65 m/s) - (35 m/s) = 30 m/s
Acceleration = (30 m/s) / (5 s)
Acceleration = 6 m/s²
a motorcar is moving with a velocity of 108 km / h and it takes 4s to stop after the brakes are applied calculate the force exerted by the brakes on the motorcar if it's mass along with the passengers is 1000 kg
Answer:
-7500 N
Explanation:
v₀ = 108 km/h = 30 m/s
v = 0 m/s
t = 4 s
a = Δv / Δt
a = (0 m/s − 30 m/s) / 4 s
a = -7.5 m/s²
F = ma
F = (1000 kg) (-7.5 m/s²)
F = -7500 N
Answer:-7500
Explanation v₀ = 108 km/h = 30 m/s
v = 0 m/s
t = 4 s
a = Δv / Δt
a = (0 m/s − 30 m/s) / 4 s
a = -7.5 m/s²
F = ma
F = (1000 kg) (-7.5 m/s²)
F = -7500 N
Wil-E-Coyote drops a bowling ball off a cliff to try to catch the Roadrunner. The cliff is
132 m high. How many seconds does it take the ball to fall to the ground?
Answer:
t = 5.19 s
Explanation:
We have,
Height of the cliff is 132 m
It is required to find the time taken by the ball to fall to the ground. Let t is the time taken. So, using equation of kinematics as :
[tex]y=ut+\dfrac{1}{2}gt^2\\\\\text{since}\ u=0\\\\y=\dfrac{1}{2}gt^2\\\\t=\sqrt{\dfrac{2y}{g}}\\\\t=\sqrt{\dfrac{2\times 132}{9.8}}\\\\t=5.19\ s[/tex]
So, it will take 5.19 seconds to fall to the ground.
8. Simple machines make a job easier to perform by
a. decreasing the amount of work
b. decreasing the amount of friction
c. decreasing the amount of force and/or changing the direction of force
d. only lower the amount of force
Answer:
C
Explanation:
Please give me concept to solve this.
Answer:
The difference in tension, between adjacent sections of the pull cable at the given conditions is 17.701 kN
Explanation:
We take the cars as moving upwards such that the resultant pulling force on the car, F, along the cable is given by the relation
[tex]F_{car}[/tex] = Upward tension force, [tex]Tension_{(upwards)}[/tex] - Downward tension force, [tex]Tension_{(downwards)}[/tex] - Component of the weight of the car along the taut cable
The parameters given are;
Mass of car, m = 2750 kg
Angle of inclination of taut cables, θ = 35°
The upward acceleration of the car, a = 0.81 m/s²
Given that the weight is acting vertically downwards, we have;
Component of the weight of the car along the taut cable = m × g × sin(θ)
∴ Component of the weight of the car along the taut cable = 2750 × 9.81 × sin (35°) = 15473.66 N
We therefore have;
[tex]F_{car}[/tex] = [tex]Tension_{(upwards)}[/tex] - [tex]Tension_{(downwards)}[/tex] - 15473.66 N
[tex]F_{car}[/tex] = m × a = 2750 × 0.81 = [tex]T_{upwards}[/tex] - [tex]T_{downwards}[/tex] - 15473.66
∴ [tex]Tension_{(upwards)}[/tex] - [tex]Tension_{(downwards)}[/tex] = 2750 × 0.81 + 15473.66 = 17701.16 N
Hence the difference in tension, [tex]Tension_{(upwards)}[/tex] - [tex]Tension_{(downwards)}[/tex] between adjacent sections of the pull cable if the cars are at the maximum permissible mass and are being accelerated up the incline = 17701.16 N or 17.701 kN.
Calcula el trabajo que realiza la fuerza de fregamiento sobre un cuerpo de 13kg que es desplaza una distáncia de 46 m si el coeficiente de fregamiento entre las superficies es de 0,45
Answer:
Los datos que tienes son:
m = 13 kg
d = 46 m
∪ = 0,45
g = 9,8 m/s²
Fr = ?
w = ?
Lo primero que haremos que calcular Fr
Fr = ∪mg
Fr = (0,45) (13 kg) (9,8 m/s²)
Fr = 57,33 N
Calculamos el trabajo realizado.
w = Fd
w = (57,33 N) (46 m)
w = 2637,18 Joules
Respuesta.
El trabajo realizado es 2637,18 Joules
Explanation:
why the weight of a body decreases with increases in distance from the earth's surface
because as the distance increases the gravitational force decreases so the weight of a body decreases
Answer:
Weight of the body decreases with increase in distance from the Earth because weight is inversely proportional to distance from the Earth which means Weight of the body decreases with increase in distance from the Earth and vice versa. Also Weight is "gravitational force exerted on the body" so as the distance from the Earth increases , the "gravitational force" decreases.
Explain two applications of resonance
PLEASEEEE HELP ME!
Answer:
in physics, resonance is a phenomenon in which a vibrating system or external force drives another system to oscillate with greater amplitude at specific frequencies. example a familiar example is a playground swing, which acts as a pendulum.
hope this helped!
Benda setinggi 3 cm diletakkan pada jarak 10 cm di depan cermin cekung yang berjari-jari
kelengkungan 10 cm. Tentukan:
Jarak bayangan
Perbesaran bayangan
Sifat bayangan
Answer:
a) Shadow distance
10 cm in front of the mirror.
b) Zoom in the shadow
The shadow formed is the same height as the object and is placed also at the centre of curvature of the mirror as shown in the attached image to this solution.
c) The nature of the shadow
The shadow formed is real, inverted, same size as the object and formed at the centre of curvature.
Explanation:
English Translation
Objects as high as 3 cm are placed at a distance of 10 cm in front of a concave mirror with 10 cm curvature. Determine:
a) Shadow distance
b) Zoom in the shadow
c) The nature of the shadow
Solution
The mirror equation is given as
(1/f) = (1/v) + (1/u)
f = focal length of the mirror = (radius of curvature)/2 = 10/2 = 5 cm
v = image distance = ?
u = object distance = 10 cm
We can then calculate the shadow' s distance from the mirror thus
(1/5) = (1/v) + (1/10)
(1/v) = 0.2 - 0.1 = 0.1
v = (1/0.1) = 10 cm
b) Zoom in the shadow
Since the object is placed at the centre of curvature, as shown in the attached image, the image is formed at a point of intersection of rays. The image formed is the same height as the object and is placed also at the centre of curvature of the mirror.
c) The nature of the shadow
Since the mirror is a concave mirror, the image is real and formed in front of the mirror. The image is also inverted and formed at the centre of curvature of the mirror.
Hope this Helps!!!
what is light rays ?
Answer:
A light ray is a line (straight or curved) that is perpendicular to the light's wavefronts
Explanation:
Have a great day.
Which statements best describe X-rays?
Answer:x rays are electromagnetic waves.
x rays are transverse waves
x rays travel at the speed of light
Explanation:
For a moving object, the force acting on the object varies directly with the objects acceleration. When a force of 24N acts on a certain object, the acceleration of the object is 3m/s^2. If the acceleration of the object becomes 10m/s^2, what is the force
Answer:
80 N
Explanation:
From the question,
F = ma .......................... Equation 1
Where F = Force, m = mass of the object, a = acceleration of the object.
make m the subject of the equation
m = F/a.................... Equation 2
Given: F = 24 N, a = 3 m/s²
Substitute into equation 2
m = 24/3
m = 8 kg.
If the acceleration of the object becomes 10 m/s²,
Substitute into equation 1
F = 10(8)
F = 80 N.
what is the defination of temperature
Answer:
Temperature is a physical property of matter that quantitatively expresses hot and cold
Explanation:
Answer:
Temperature is the degree of hotness or coldness in a body
Explanation:
it is measured by the Average kinetic energy of the body. It is independent of the mass,it's measured in °C(Celsius),K(kelvin),°F(Fahrenheit)
When heat is converted into another form of energy, the total amount of energy is constant. Which law best illustrates this statement?
A.
the first law of thermodynamics
B.
the second law of thermodynamics
C.
the third law of thermodynamics
D.
none of the above
Answer:
A
Explanation:
This is the first law of thermodynamics and it's called the law of conservation of energy
PLEASE HELP. Really important
Explanation:
2) C would need the least effort, because the longer the effort distance, the least the effort applied.
Please explain it’s in the photo
Answer:
Since air resistance actually stops vehicles and goes in a vector opposite to the direction of the vehicle and slows it down. Vehicles would want to make vehicles aerodynamic. Many cars bump into air molecules therefore making air resistance. Aerodynamic cars will lesser the allowance of bumping into said molecules. Thats why cars like to cut down on air resistance
Air resistance is friction.
-- Friction steals kinetic energy.
-- A car gets kinetic energy by burning gasoline, and uses the kinetic energy to get where it needs to go.
-- If anything steals the car's kinetic energy, then the car has to burn more gasoline to get where it needs to go.
-- Gasoline costs money.
-- Anything that steals a car's kinetic energy costs you more money to operate the car.
(Another thing that takes kinetic energy away from the car is the car's brakes. The driver uses the brakes when he WANTS to slow down or stop, so it's not stealing, but it still costs kinetic energy and money.)
Un movil pasa por el punto A en direccion hacia B (350cm más adelante) y, luego, sigue hasta el punto C. Sabiendo que pasa por B a las 11:42:38 y por C a las 11:43:16, completando un tiempo total de recorrido de 3min 47s, calule la distancia entre B y C y a la hora a la que paso por el punto A.
Explanation:
PRIMERO HACES EL RECUENTO DEL TIEMPO Y LO CONVIERTES EN
SEGUNDOS Y ENTONCES
t = 227 s [tex]t_{AB}[/tex] = 227 S - 38 s = 189 s
[tex]t_{BC}[/tex] = 38 s
LUEGO USANDO LA ECUACIÓN DE GALILEO GALILEI SSUPONIENDO
QUE EL MOVIL VIAJA A VELOCIDAD CONSTANTE
v = 3.50 m/189 s = 0.0185 m/s
PARA LA DISTANCIA NTRE B Y C
[tex]x_{BC}[/tex] = 0.0185 m/S( 38 s) = 0.703 m
LA HORA EN QUE EL MOVIL PASA POR A ES
11:43:15 - 38 s - 189 s = 11:39:29
can there be shadows at night outside?
Answer:
To see a shadow there most be light provided, even if it's night and there are lights, we can still see the shadow but if there is no light, we can't.
Hope it helped (:
Answer: yes of course, but there should be some light to make or see shadows.
A train starts from its station and it
velocity reaches 200m/s in 5
seconds. What is its acceleration?
a. 400m/s
b. 40m/s2
c. 4.5m/s2
d. Initial velocity is missing
Answer:
b. 40m/s2
Explanation:
Acceleration is calculated by dividing velocity over time. Therefore 200m/s by 5s equals 40m/s2
Answer:
B
Explanation:
v = vo + at
200 = 0 + a*5
200 = 5a
a = 200/5 = 40 m/s²
initial velocity (vo) is 0 because it says it start from station
Explain how series circuits use current and voltage and Explain how parallel circuits use current and voltage
'''In a series circuit, the sum of the voltages consumed by each individual resistance is equal to the source voltage. Components connected in parallel are connected along multiple paths so that the current can split up; the same voltage is applied to each component.''
An object with more mass has more kinetic energy than an object with less
mass, if both objects are moving
OA) at the same speed
OB) in the same direction
OC) in opposite directions
Explanation:
The kinetic energy of an object is given in terms of its mass and object as :
[tex]K=\dfrac{1}{2}mv^2[/tex]
An object with more mass has more kinetic energy. An object with less mass, if both objects are moving at the same speed, in opposite directions, will have less kinetic energy. The square of v will give positive number.
A lonely child is swinging on a rusty old swing set, as seen in the image provided. If friction does 145 J of work slowing the swing, what is the maximum speed she can reach?
Answer:
2.331
Explanation:
It just the change of Energy from potential (PE) to kinetic (KE)
PE on A = PE on B + KE on B + friction works (Wf)
mg(ha) = mg(hb) + ½mv² + Wf
35 * 9.8 * 1.5 = 35 * 9.8 * 0.8 + ½ * 35 * v² + 145
514.5 = 274.4 + 17.5v² + 145
514.5 - 274.4 - 145 = 17.5v²
17v² = 95.1
v² = 5.434
v =√5.434 = 2.331 m/s
The atomic number of a nucleus decreases during which nuclear reactions?
A. Nuclear fission and alpha decay
B. Nuclear fusion and beta decay (positron emission)
C. Nuclear fission and beta decay (electron emission)
D. Nuclear fusion and alpha decay
The atomic number of a nucleus decreases during:
A. Nuclear fission and alpha decay
What happens in alpha decay?Alpha decay is an atomic rot process where a shaky core changes to one more component by shooting out a molecule made out of 2 protons and 2 neutrons. This catapulted molecule is known as an alpha molecule and is just a helium core.
It changes or 'rots' into an alternate nuclear core, with a mass number that is decreased by four and a nuclear number that is diminished by two.
Thus, option A is correct.
Find more information about Alpha decay here:
brainly.com/question/13512293
calculate the pressure exerted by a man having mass 50 kg standing on one feet having area 500cm2
Answer:
9800 Pa
Explanation:
Data: pressure-?
Force- mass ×acceleration
= 50× 9.8m/s^2
=490N
Area= 500cm^2=0.05m^2
pressure= force/ area
p=F/A
P= (490N)/( 0.05m^2)
=9800 Pa
a linear function has the same y-intercept as x + 4y equals 16 and it's graph contains the point (4,5). Find the slope of the linear function.
Answer: [tex]\bold{\text{Slope (m)}=\dfrac{1}{4}}[/tex]
Explanation:
A linear equation is of the form: y = mx + b where
m is the slopeb is the y-intercept (where it crosses the y-axis)x + 4y = 16
4y = -x + 16
[tex]y = -\dfrac{1}{4}x+\dfrac{16}{4}[/tex]
[tex]y=-\dfrac{1}{4}x+4[/tex]
The y-intercept (b) = 4
Next, find the slope given point (4, 5) and b = 4
[tex]y=mx+b\\\\5=m(4)+4\\\\1=4m\\\\\dfrac{1}{4}=m\\\\\\\\\large\boxed{Slope (m)=\dfrac{1}{4}}[/tex]
if the resistance of a car headlight is 15 ohm and the current through it is 0.60, what is the voltage across the headlight?
Answer:
9 volts (assuming 0.60 is in Amperes)
Explanation:
Recall that Ohms law can be expressed as
V = IR, where
V = voltage,
I = current (given as 0.6. I'm going to assume that the units is Amperes because it is not given)
R = resistance (given as 15 ohm)
substituting the above values into the formula
V = IR
V = (0.6)(15)
V = 9 Volts
An object rotates describing a horizontal circumference when subjected to a centripetal force F. What centripetal force will act on the object if the radius of the circle is doubled and the kinetic energy of the object is halved? A) F/4 B) F/2 C) F D) 4F please explain this to me : (
Answer:
Option A: F/4
Explanation:
Centripetal force, [tex]F = \frac{mv^{2} }{r}[/tex]
Where v = speed
r = radius
Since Kinetic Energy, [tex]E_{k} = 0.5 mv^{2}[/tex]
Writing centripetal force in terms of kinetic energy, [tex]F = \frac{2 E_k}{r}[/tex]
If the initial radius of the circle, r₁ =r
The doubled radius, r₂ = 2r
If the initial kinetic energy, [tex]KE_1 = E_{k}[/tex]
The halved kinetic energy, [tex]KE_2 = 0.5E_{k}[/tex]
Therefore, the new Centripetal force becomes:
[tex]F_{2} = \frac{2(0.5 E_k)}{2r} \\F_{2} = \frac{0.5 E_k}{r}\\F_{2} =\frac{1}{4} * \frac{2 E_k}{r}\\Since, F = \frac{2 E_k}{r} \\F_{2} =\frac{1}{4} * F\\F_{2} =\frac{F}{4}[/tex]
A student claims that water's polarity is the reason it has a high specific heat. What method could the student use to test his claim? Perform research to see if other polar molecules have high specific heat Measure how much energy it takes to increase the temperature of water by one degree Mix water with an acid and test the new specific heat Determine how dissolving salt in water affects the specific heat
Answer:
B
Explanation:
The method used by the student to test his claim is determine how dissolving salt in water affects the specific heat. The correct option is fourth.
What is specific heat?The specific heat is the amount of heat required to change the temperature by 1°C. It is denoted by C.
A student claims that water's polarity is the reason it has a high specific heat.
Polarity is determined by the salt dissolved in water. So, to determine how dissolving salt in water affects the specific heat is best method.
Thus, the fourth option is correct.
Learn more about specific heat.
https://brainly.com/question/11297584
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plzzzzzzz help me quick
Explanation:
in the first thing we are allowing bacteria to grow
in the second one we are killing it
Write down any four points that should be considered during household wiring
Answer:
USE RUBBER CLOVES
USE A PLIER
USE CONDUCTIVE WIRES
SWITHC OFF THE MAIN SWITCH WHILE WIRRING
Explanation:
What is the force experienced when a 5.0 kg mass is accelerated at 7.5 m/s??
Answer:
F = 37.5 N
Explanation:
It is given that,
Mass of the object is 5 kg
Acceleration of the object is 7.5 m/s²
We need to find the force experienced by the object. The force is given by the product of mass and acceleration of an object. So,
F = m
[tex]F=5\times 7.5\\\\F=37.5\ N[/tex]
So, the force acting on the object is 37.5 N.
