# Physics

1. ### A person pushes a box. He applies a force of 400 newtons, and he pushes the box for a distance of 4 meters. After he stops pushing, the box slides forward another meter. How much work was done by the person?

• 100 joules • 2,000 joules • 1,600 joules

3. ### 1) can the position-time graph for the motion of an object be a horizontal line?explain

- so its yes? 2) can the positon-time graph bea vertical line, explain -so its yes

4. ### A parallel-plate capacitor with air between the plates has an area A= 2.00 x 10^-4 m^2 and a plate

separation d = 1.00 mm. Find its capacitance.

5. ### If 500 J of work are required to carry a charged particle between two points with a potential difference of 40V, the magnitude of the charge on the particle is:

a) 0.040 C b) 12.5 C c) 20C D) cannot be computed unless the path is give e) none of these My

8. ### Radioactive Decay Energy Quick Check

Polonium has a large, unstable nucleus. Through which process is it most likely to become stable? gamma decay beta-plus decay beta-minus decay alpha decay(✔️) Which type of energy does alpha decay generate? Potential

15. ### what forms of energy are involved in the following situations? (choices: kinetic energy, potential energy - gravitational potential energy, elastic potential energy)

a. a bicycle coasting along a level road b. heating water c. throwing a football d. winding

16. ### A) A 600 kg steel beam is supported by the two ropes shown in (Figure 1). Calculate the tension in the rope.

Express your answer to two significant figures and include the appropriate units. B) The rope can support a maximum tension of 3200 N . Is this rope

20. ### How many days does it take for a perfect blackbody cube (0.0100m on a side, 30.0 degree C)to radiate the same amount of energy that a one-hundred-watt light bulb uses in one hour?

I got no idea to do it. Please give me some hints!!!Thanks!!!

24. ### A stationary source produces a sound wave at a frequency of 100 Hz. The wave travels at 1125 feet per second. A car is moving toward the sound

source at a speed of 200 feet per second. Item 3 What is the wavelength of the stationary sound source and the

25. ### A wheel with rotational inertia I is mounted on a fixed, fricitonless axle. The angular speed w of the wheel is inccreased from zero to w_f in a time interval T.

1: What is the average net torque on the wheel during the time interval, T? a) w_f/T b)w_f/T^2

27. ### A receiving antenna becomes misaligned by 30° to its original position. The power of the received signal in this new position is 12µW.

Wavelength = 0.016 m I calculated the power received in the original position as 1.04 x 10^-5 W What I need to find out

34. ### The gravitational field strenght on the moon is 1.63N/kg. If a rock on the moon weights 2000N, how much does the same rock weigh on the earth?

Which of the following energy forms is associated with an object in motion? a. potential energy b. elastic potential energy c. nonmechanical energy d. kinetic energy i think its B Which of the following energy forms is associated with an

36. ### Thanks for any help :)

Four 20 ohm resistors are connected in parallel and the combination is connected to a 20V emf device. The current is: A) 0.25A B) 1.0 A C) 4.0 A D) 5.0 A E) 100 E Parallel circuits: I know that the voltage is 20V and the Resistance is

37. ### In the parallel circuit, if the current put out

by the battery is 3 A and the current through R1 is 1 A, what is the current through R2?

38. ### A horse runs 15 m [N 23° E] and then 32 m [S 35° E]. What is the total displacement of the horse?

I can't even visualise this... My friend told me the basic steps on how to solve it, but I got the wrong answer anyways... d1 = 15 m [N 23° E] d1x = 15m sin

39. ### A 72.0 kg swimmer jumps into the old swimming hole from a tree limb that is 4.00 m above the water.

Part A- Use energy conservation to find his speed just as he hits the water if he just holds his nose and drops in. Part B- Use energy conservation to find

43. ### The hydrogen atom contains a proton, mass 1.67 10-27 kg, and an electron, mass 9.11 10-31 kg. The average distance between them is 5.3 10-11 m. The charge of the proton is the same size, opposite sign of the electron.

a)What is the magnitude of the average

44. ### The linear impulse delivered by the hit of a boxer is 97.7 N·s during the 0.368 s of contact.

What is the magnitude of the average force exerted on the glove by the other boxer? Answer in units of N.

46. ### A bike wheel rotates uniformly through 2 revolutions in 3 seconds.

a) what is the period of the wheel's rotation? T=3rev/2s=1.5s b) what is the frequency of the wheel's rotation? (in Hertz) f=1/T =1/1.5 =.666Hz c) what is the angular speed of the

47. ### A 15kg box is resting on a hill forming an angle with the horizontal. The coefficient of static friction for the box on the surface is 0.45. Calculate the maximum angle of the incline before the box starts to move.

Steps included would be great, I have the

48. ### Bob is pulling a 30kg filing cabinet with a force of 200N , but the filing cabinet refuses to move. The coefficient of static friction between the filing cabinet and the floor is 0.80.

What is the magnitude of the friction force on the filing cabinet?

53. ### I need help with this question with explanation. Thanks

A particle of mass m starts from rest at position x = 0 and time t = 0. It moves along the positive x-axis under the influence of a single force Fx = bt, where b is a constant. The velocity v of the

56. ### A 300 g block on a 54.0 cm -long string swings in a circle on a horizontal, frictionless table at 85.0 rpm .

What is the speed of the block? Express your answer with the appropriate units. What is the tension in the string? Express your answer with the

57. ### A box with mass 13.0 kg moves on a ramp that is inclined at an angle of 55.0∘ above the horizontal. The coefficient of kinetic friction between the box and the ramp surface is μk = 0.300.

FIND A) Calculate the magnitude of the acceleration of the box if

64. ### Two point charges that have charge values of 4.0 X 10^-6 C and -8.0 X 10^-6 C, respectively, are separated by 2.4 X 10^-2 m. What is the mutual force between them, given that kC = 8.99 X 10^9 Nm^2/C^2?

I got the Felectric as -5.0 X 10^2 N, but I'm not sure

66. ### Problem 2- A 350 kg roller coaster starts from rest at point A and slides down the frictionless loop-the-loop shown in the figure.

a) How fast is the roller coaster moving at point B? b) How hard does it press against the track at point B?

68. ### Ammeter 1 reads 0.20 A.

a. What should ammeter 3 indicate? b. What should ammeter 4 indicate? Given: RA = 22-OHM RB = 13-OHM A1 = 0.20 A Ammeter 2 reads 0.15A. a. Find the voltage across the 22-ohm resistor? b. Find the voltage across the 15-ohm resistor?

70. ### Consider the circuit shown in the figure below. (Assume R1 = 12.0 Ω and R2 = 6.00 Ω.)

Read this for the figure - A rectangular circuit begins at its left side at a 25.0 V battery with the positive terminal on top. From the battery, the circuit extends up

78. ### A 2.1kg brass ball is transported to the Moon.

a)What is the mass of the brass ball on the earth and on the moon? Wouldn't it be 2.1kg for the earth as well as for the moon? b)Determing the weight of thee brass ball on the earth. F_g=(G*m_ball*m_earth)/r^2

82. ### An inductor used in a dc power supply has an inductance of 12 H and a resistance of 180 ohms and carries a current of .300 A. (a) How much energy is stored in the magnetic field? (b) At what rate is thermal energy developed in the inductor?

ok once again I

88. ### A box accidentally falls from the back of a truck and hits the ground with a speed of 15m/s. It slides along the ground for a distance of 45 m before coming to rest. Determine

a) the length of time the box slides before stopping c) the time it takes to

89. ### A 10.-newton force is required to hold a

stretched spring 0.20 meter from its rest position. What is the potential energy stored in the stretched spring?

93. ### A block of mass m = 2.00 kg rests on the left edge of a block of mass M = 8.00 kg. The

coefficient of kinetic friction between the two blocks is 0.300, and the surface on which the 8.00- kg block rests is frictionless. A constant horizontal force of

95. ### A horizontal pipe narrows from a diameter of 10 to 5 cm. For an incompressible fluid flowing from the larger diameter to the smaller:

Question 5 options: 1.the velocity and pressure both increase. 2.the velocity increases and the pressure decreases. 3.the

96. ### The period of motion of an object-spring system is T = 0.474 s when an object of mass m = 296 g is attached to the spring.

(a) Find the frequency of motion in hertz. _______Hz (b) Find the force constant of the spring. _______N/m (c) If the total energy of

97. ### A 0.006-kg bullet traveling horizontally with a speed of 1.00 103 m/s enters an 21.1-kg door, imbedding itself 10.4 cm from the side opposite the hinges as in the figure below. The 1.00-m-wide door is free to swing on its hinges.

(c) At what angular speed