PHYSICS COLLEGE

A soccer ball is kicked straight upwards with an initial vertical speed of 8.0\,\dfrac{\text m}{\text s}8.0 s m 8, point, 0, start fraction, start text, m, end text, divided by, start text, s, end text, end fraction. We can ignore air resistance. How long does it take the ball to have a downwards speed of 4.0\,\dfrac{\text m}{\text s}4.0 s m 4, point, 0, start fraction, start text, m, end text, divided by, start text, s, end text, end fraction?

Answers

Answer 1

Answer:

Answer:

1.2 s

Explanation:

Given:

v₀ = 8.0 m/s

v = -4.0 m/s

a = -10 m/s²

Find: t

v = at + v₀

(-4.0 m/s) = (-10 m/s²) t + (8.0 m/s)

t = 1.2 s

Related Questions

Help me with my physics, please
5. A 55-kg swimmer is standing on a stationary 210-kg floating raft. The swimmer then runs off the raft horizontally with the velocity of +4.6 m/s relative to the shore. Find the recoil velocity that the raft would have if there were no friction and resistance due to the water.
An isotropic point source emits light at wavelength 500 nm, at the rate of 185 W. A light detector is positioned 380 m from the source. What is the maximum rate ∂B/∂t at which the magnetic component of the light changes with time at the detector's location?
Light of wavelength 608.0 nm is incident on a narrow slit. The diffraction pattern is viewed on a screen 88.5 cm from the slit. The distance on the screen between the fifth order minimum and the central maximum is 1.61 cm. What is the width of the slit?
Find an expression for the center of mass of a solid hemisphere, given as the distance R from the center of the flat part of the hemisphere. Express your answer in terms of R. Express the coefficients using three significant figures.

Assume that the speed of light in a vacuum has the hypothetical value of 18.0 m/s. A car is moving at a constant speed of 14.0 m/s along a straight road. A home owner sitting on his porch sees the car pass between two telephone poles in 8.89 s. How much time does the driver of the car measure for his trip between the poles?

Answers

Answer:

Observed time, t = 5.58 s

Explanation:

Given that,

Speed of light in a vacuum has the hypothetical value of, c = 18 m/s

Speed of car, v = 14 m/s along a straight road.

A home owner sitting on his porch sees the car pass between two telephone poles in 8.89 s.

We need to find the time the driver of the car measure for his trip between the poles. The relation between real and observed time is given by :

$T=\frac{t}{\sqrt{1-(v^2)/(c^2)} }$

t is observed time.

$t=T* \sqrt{1-(v^2)/(c^2)} \n\nt=8.89* \sqrt{1-(14^2)/(18^2)} \n\nt=5.58\ s$

So, the time observed by the driver of the car measure for his trip between the poles is 5.58 seconds.

The Golden Gate Bridge in San Francisco has a main span of length 1.28 km, one of the longest in the world. Imagine that a steel wire with this length and a cross-sectional area of 3.10 ✕ 10^−6 m^2 is laid on the bridge deck with its ends attached to the towers of the bridge, on a summer day when the temperature of the wire is 43.0°C. When winter arrives, the towers stay the same distance apart and the bridge deck keeps the same shape as its expansion joints open. When the temperature drops to −10.0°C, what is the tension in the wire? Take Young's modulus for steel to be 20.0 ✕ 10^10 N/m^2. (Assume the coefficient of thermal expansion of steel is 11 ✕ 10−6 (°C)−1.)

Answers

Answer:

361.46 N

Explanation:

$\alpha$ = Coefficient of thermal expansion = $11* 10^(-6)\ /^(\circ)C$

Y = Young's modulus for steel = $20* 10^(10)\ Pa$

A = Area = $3.1* 10^(-6)\ m^2$

$L_0$ = Original length = 1.28 km

$\Delta T$ = Change in temperature = $45-(-10)$

Length contraction is given by

$\Delta L=\alpha L_0\Delta T$

Also,

$\Delta L=(L_0T)/(YA)$

$\alpha L_0\Delta T=(L_0T)/(YA)\n\Rightarrow T=\alpha \Delta TYA\n\Rightarrow T=11* 10^(-6)* (43-(-10))* 20* 10^(10) * 3.1* 10^(-6)\n\Rightarrow T=361.46\ N$

The tension in the wire is 361.46 N

Which of the following is a TRUE statement? a. It is possible for heat to flow spontaneously from a hot body to a cold one or from a cold one to a hot one, depending on whether or not the process is reversible or irreversible.
b. It is not possible to convert work entirely into heat.
c. The second law of thermodynamics is a consequence of the first law of thermodynamics.
d. It is impossible to transfer heat from a cooler to a hotter body.
e. All of these statements are false.

Answers

Answer:

e. All of these statements are false.

Explanation:

As we know that heat transfer take place from high temperature to low temperature.

It is possible to convert all work into heat but it is not possible to convert all heat in to work some heat will be reject to the surrounding.

The first law of thermodynamics is the energy conservation law.

Second law of thermodynamics states that it is impossible to construct a device which convert all energy into work without rejecting the heat to the surrounding.

By using heat pump ,heat can transfer from cooler body to the hotter body.

Therefore all the answer is False.

A uniform, solid sphere of radius 3.75 cm and mass 4.00 kg starts with a purely translational speed of 1.75 m/s at the top of an inclined plane. The surface of the incline is 3.00 m long, and is tilted at an angle of 26.0∘ with respect to the horizontal. Assuming the sphere rolls without slipping down the incline, calculate the sphere's final translational speed ????2 at the bottom of the ramp.

Answers

Answer:

v_2=4.53m/s $v_2=4.53m/s$

Explanation:

In order to solve the exercise it is necessary to apply the energy conservation equation,

The equation says the following,

$mgdsin(\theta)+(1)/(2)mv^2_1=(1)/(2)mv^2_2+(1)/(2)Iw^2$

Replacing the formula for I of a sphere, we have

$mgdsin(\theta)+(1)/(2)mv^2_1=(1)/(2)mv^2_2+(1)/(2)(2)/(5)mr^2((v_2)/(r))^2$

$mgdsin(\theta)+(1)/(2)mv^2_1=(1)/(2)mv^2_2+(1)/(5)mv^2_2=(7)/(10)mv^2_2$

$(10)/(7)gdsin(\theta)+(5)/(7)v^2_1=v^2_2$

In this way we get the expression

$v_2=\sqrt{(10)/(7)gdsin(\theta)+(5)/(7)v^2_1}$

We proceed to replace with the given values and obtain that

$v_2=\sqrt{(10)/(7)*9.8*3sin(26))+(5)/(7)*1.75^2}$

$v_2=4.53m/s$

v_2=4.53m/sv_2=4.53m/s

The equation says the following,

mgdsin(0) + 1/2mv2/1 = 1/2mv2/2 + 1/2Iw^2

Replacing the formula for I of a sphere,

mgdsin(0) + 1/2mv2/1 = 1/2mv2/2 + 1/2 2/5mr^2 (v2/r)^2

mgdsin(0) + 1/2mv2/1 = 1/2mv2/2 + 1/5mv2/2 = 7/10mv2/2

10/7gdsin(0) + 5/7v2/1 = v2/2

In this way, we get the expression

v2 = sqrt(10/7gdsin(0) + 5/7v2/1)

v2 = sqrt(10/7 * 9.8 * 3sin(26)) + 5/7 * 1.75^2

v2 = 4.53m/s

Further Explanation

The ball that rolls on the plane will experience two movements at once, namely the rotation of the axis of the ball and the translational field being traversed. Therefore, objects that do rolling motion have a rotational equation and a translational equation. The amount of kinetic energy possessed by the rolling body is the amount of rotational kinetic energy and translational kinetic energy. You will here learn about the ball rolling on a plane and incline.

An object can experience translational motion or rotational motion. Translational motion is the motion of objects whose direction is straight or curved. In translational motion using the concept of Newton II's law. While the rotational motion is the motion that has a rotation of a particular shaft. Rotational motion is caused by the torque, which is the tendency of a force to rotate a rigid body against a particular pivot point.

Learn More

Object Experience brainly.com/question/13696852

The ball that rolls brainly.com/question/13707126

Details

Grade: College

Subject: Physics

Keyword: object, ball, roll

15.Restore the battery setting to 10 V. Now change the number of loops from 4 to 3. Explain what happens to the magnitude and direction of the magnetic field. Now change to 2 loops, then to 1 loop. What do you observe the relationship to be between the magnitude of the magnetic field and the number of loops for the same current

Answers

Answer:

we see it is a linear relationship.

Explanation:

The magnetic flux is u solenoid is

B = μ₀ N/L I

where N is the number of loops, L the length and I the current

By applying this expression to our case we have that the current is the same in all cases and we can assume the constant length. Consequently we see that the magnitude of the magnetic field decreases with the number of loops

B = (μ₀ I / L) N

the amount between paracentesis constant, in the case of 4 loop the field is worth

B = cte 4

N B

4 4 cte

3 3 cte

2 2 cte

1 1 cte

as we see it is a linear relationship.

In addition, this effect for such a small number of turns the direction of the field that is parallel to the normal of the lines will oscillate,

Q.1- Find the distance travelled by a particle moving in a straight line with uniform acceleration, in the 10th unit of time.

Answers

Answer:

If the acceleration is constant, the movements equations are:

a(t) = A.

for the velocity we can integrate over time:

v(t) = A*t + v0

where v0 is a constant of integration (the initial velocity), for the distance traveled between t = 0 units and t = 10 units, we can solve the integral:

$\int\limits^(10)_0 {A*t + v0} \, dt = ((A/2)10^2 + v0*10) = (A*50 + v0*10)$

Where to obtain the actual distance you can replace the constant acceleration A and the initial velocity v0.

Other Questions

A stock person at the local grocery store has a job consisting of the following five segments:1) picking up boxes of tomatoes from the stockroom floor2)accelerating to a comfortable speed.3) Carring the boxes to the tomato display at constant speed.4)decelerating to a stop.5) lowering the boxes slowly to the floor.During which of the five segments of the job does the stock person do positive work on the boxes?A) (2) and (3)B(1) and (2)C) (1) onlyD) (1), (2), (4) and (5)E) (1) and (5)

Air enters an adiabatic compressor at 104 kPa and 292 K and exits at a temperature of 565 K. Determine the power (kW) for the compressor if the inlet volumetric flow rate is 0.15 m3/s. Use constant specific heats evaluated at 300 K.

What problem did Katherine face in checking other people’s calculations in the movie ¨Hidden figures¨

How do you define 'heat' and 'temperature'