# Posts by physics

Total # Posts: 427

**science **

Two charges repel each other with a force of 10-5newton when they are 20cm apart. what is the force on each of them are i 3cm apart and ii when they are 100cm

*March 17, 2017*

**physics**

A 60kg boy climbs 70 fligts of stairs each 20cm high in one minute how much powers is developed?

*March 3, 2017*

**Physics**

A Ball of Mass 0.5kg Moving At 10m/s Collide With Another Ball Of Equal mass At Rest.If The Two Balls Move Together After The Impact Calculate Their common Velocity

*February 22, 2017*

**projectile motion**

A stone of 2kg is projecter vertically as a velocity of 5m/s at an angle of 60.calculate,the time taking?the maximum hight?the range

*February 12, 2017*

**Math**

yea of course

*December 15, 2016*

**PHYSICS**

Charlie now moved onto the next hole where he hit the ball with an initial speed of 30 m s-1 and at an angle of 60 degrees. This time the ball lands with a speed of 17.3 m s-1. Use g = 9.8 m s-2.

*December 15, 2016*

**PHYSICS**

Terry hit his 26 g golf ball so that it has an initial velocity of 33 m s-1 travelling at an angle of 26 to the horizon. If the ball lands at the same height it was struck, how far will it travel? Use g = 9.8 m s-2.

*December 15, 2016*

**p[hysics**

A soccer ball was kicked off a cliff that was h = 8.4 m above the ground. The ball was kicked at a speed of 25 m s-1 and an angle of 20 to the horizon. What is magnitude of the horizontal displacement of the ball? Use g = 9.8 m s-2.

*December 15, 2016*

**PHYSICS HELP!!!!!**

A soccer ball was kicked off a cliff that was h = 8.4 m above the ground. The ball was kicked at a speed of 25 m s-1 and an angle of 20 to the horizon. What is magnitude of the horizontal displacement of the ball? Use g = 9.8 m s-2. proper equation and help plz

*December 15, 2016*

**Physics FRICTION FORCE AND N-2ND LAW**

A balloon has a weight of 1250 N, and the lifting force on it is 3525N. If the air resistance is 15N, what is the acceleration of the balloon? (Notice fg=mg) 3525-15=3515 3515/1250= 2.81 ???? A pulling force on a case is 1653 N while the friction force is 765 N on the case. If...

*November 6, 2016*

**Physics PROJECTILE AND CIRCULAR MOTION**

So for the first one I got 0.78. The second 23 horizontal and 20 vertical. The third I got 8.64 And fourth I got 96 ??

*November 6, 2016*

**Physics PROJECTILE AND CIRCULAR MOTION**

1.13g plastic stopper is attached to a 0.93-m string. The stopper is swung in a horizontal circle, making one revolution in 1.18s(period T). Find the tension force(equivalent to the centripetal force)exerted by the string on the stopper? (V=2(pie)r/T)? 2. A football is thrown ...

*November 6, 2016*

**science**

a stone weighing 0.2kg tied to the end of the string 0.6m long whorld in a horizontal circle in a speed of 150 revolutions per minute. calculte the tension and string

*November 1, 2016*

**Math**

A car is accelerated from rest to a speed of 35m/s over a distance of 18m. What is the car's acceleration? okay so I thought that I need to use the a= Vf-Vi/T2-T1. 18m-0s/35m/s-0s = 0.5?? I don't think I did this right.

*September 27, 2016*

**Math**

A student sits in the school bus traveling to her school. If the student stands up and moves at 1.5m/s toward the rear of the bus that travels at 10m/s to the east,what is her velocity relative to the observer on the side of the road? If she moves at 2.1 m/s toward the front ...

*September 20, 2016*

**Math**

A student sits in the school bus traveling to her school. If the student stands up and moves at 1.5m/s toward the rear of the bus that travels at 10m/s to the east,what is her velocity relative to the observer on the side of the road? If she moves at 2.1 m/s toward the front ...

*September 20, 2016*

**Math**

A swimmer wants to swim at a speed of 3 m/s north across a river flowing at 0.8m/s,east. What is the actual direction and quantity of the swimmer's motion? ((I have no idea where to even start))

*September 20, 2016*

**PHYSICS**

In an archery practice an arrow was realesed from a bow with a velocity of 20m/s it strikes and slopes find at what rate the aarrow was aaccelarated

*September 18, 2016*

**Two bus trvl in opposite direction frm that same rtarting point.if d speed of 1 is twice d speed of d other and de 240km**

Apart at the end of one hour,what is the speed of each bus?

*September 7, 2016*

**Physics**

during a race,a dragster is 200 meters from the finish line when something goes wrong and its stops accelerating.it travels at a constant velocity of45 meters per second for 3seconds to try to finish the race.How far from the finish line is the dragster after 3 seconds?

*July 26, 2016*

**physics**

Using pinch effect describe magnetic confinement of plasma

*May 26, 2016*

**Kaycee**

A charge q equals to 3.4c is located at x equal 2m and y equal 2m and a second charge q2 equal to 2.7c is located at x equal 4m and y equal -4m..where must a third charge q be placed such that the resolutant force on it is zero .

*May 9, 2016*

**Physics**

A model rocket was launched Amazon man of its height and horizontal distance from launch pad where they can as shown in the table

*May 5, 2016*

**Physics**

A cyclist starts from rest and accelerates at 2m/s2, for 2second. Her velocity remains constant for the following 4second. The brakes are then applied and the bicycle decelerates uniformly until it comes to rest after 10 second. Find(a) the distance moved during each stage of ...

*March 29, 2016*

**Physics**

A car is driving with a velocity of 108km/h suddenly a child crosses the road 100m in frond of the car. the driver applies brakes and comes to a stop in 5 second. Calculate the acceleration of the car

*March 29, 2016*

**luma**

A rock weighs 100 N in air and has a volume of 0.00312 m^3. What is its apparent weight when submerged in water? The acceleration of gravity is 9.8 m/s^2. Answer in units of N.

*January 27, 2016*

**Physics**

I need physics help. I don't understand how to do these questions. Can someone show me what I should use? and explain. I'll do calculations by myself. A stationary curling stone is struck in a glancing collision by a second curling stone of equal mass. If the first ...

*January 26, 2016*

**physics**

A bus of mass 2500kg goes round a corner of radius 50m at a speed of 5m/s. what force is needed for the bus to go round the corner?

*January 26, 2016*

**SIERRA**

a fullback having a mass of 9.0x10^1 kg is running at 4.5 m/s [E]. He is hit by a linebacker and 1.2 s later is moving backwards at 1.5 m/s [W].Find: a) the impulse imparted to the fullback B) the average force exerted on the fullback by the linebacker my work: impulse is p so...

*January 13, 2016*

**Physics help!!!!!!!!!!!**

What are some good websites/youtube videos for learning grade 12 Physics - Dynamics strand: Kinematics (1D & 2D motion), Vectors, Relative Motion, Projectile motion, Frames of reference, Forces, Free Body Diagrams, Problem solving - Force of Friction, Normal Force, Pulleys, ...

*December 10, 2015*

**physics**

Assume a cyclist of weight mg can exert a force on the pedals equal to 0.90 mg on the average. If the pedals rotate in a circle of radius 18 cm, the wheels have a radius of 34 cm, and the front and back sprockets on which the chain runs have 42 and 19 teeth respectively (Fig. ...

*November 16, 2015*

**universitu**

A tire 0.50meter in radius rotates at aconstant rate of 200 revolution per minute .find the speed & accelaration of asmall stone lodged in the tread of the tire(on its outer edge)

*November 5, 2015*

**Crystal**

So this is the problem: A comet is in an elliptical orbit around our Sun. At its point of closest approach, it is moving at 6.3x10^4 m/s and is 4.2x10^10m away from the sun. When it is at the farthest distance, 7.5x10^12m away, how fast is it going? This is what I did K1+U1=K2...

*November 4, 2015*

**mastering physics**

An airplane pilot wishes to fly due west. A wind of 90.0 km/h is blowing toward the south.If the airspeed of the plane (its speed in still air) is 305.0 km/h , in which direction should the pilot head?

*October 29, 2015*

**physics**

You are driving on a very long, very straight 2 lane road, stuck behind a lorry which travels at a constant 75 km/hour. You want to overtake the lorry, which has a length of 12.0 m. You car is 3.8 m long. To overtake the lorry, and to do this safely, you need to move to the ...

*October 17, 2015*

**science**

do yourself

*October 4, 2015*

**Physics**

4.85pm

*June 17, 2015*

**Honors Physics**

Emily makes 0.250 kg of hot tea at 99.0°C. How much ice at 0.00°C must she add to the tea so that the mixture reaches a final temp. of 8.00°C? (You may treat the tea as if its water.) My work: (0.25)(4186)(91) + m(4186)(-8)(3.35 ×10^5)=0 My answer: 0.316 It ...

*June 1, 2015*

**science**

the resultant of two forces 13n and 20 n is f if the first forces is doubled the resultant is also doubled to 2f find the angle betwen the two forces

*May 18, 2015*

**PHYSICS**

Consider a classroom 10.0m long by 6.0m wide by 4.0m high at "room temperature" 20.C and 1.0 atmosphere. A) How many moles of gas are contained in the room? B) Assuming an average molecular weight of 28, what is the mass of the room air?

*May 7, 2015*

**quantum**

Consider a particle with mass m bound to a potential v(x) = k^2|x|. Using the WKB quantization condition, find the energy eigenvalues .

*April 4, 2015*

**PHYSICS**

The gravitational forces of the Earth and the Moon are attractive, so there must be a point on a line joining their centers where the gravitational forces on an object cancel. How far is this distance from the Earth's center?

*March 15, 2015*

**Marianne**

Fill in the blank: The electrons follow a ________ path when they are deflected in a magnetic field due to the magnetic force.

*March 13, 2015*

**science**

A sandbag falls from a hot air balloon that is rising with a constant velocity of 15m.s 1)What is the acceleration of the bag the moment it fell from the hot air balloon? 2)What is the acceleration of the hot air balloon the moment the sandbag fell from it? 3)What is the ...

*March 1, 2015*

**physics(urgent answer pls)**

PREPARATORY SCHOOL GRADE 11

*March 1, 2015*

**physics**

find the resistance of 134m of No.20 copper wire at 20 degrees C (p=1.72x10^-6Ohom cm , A= 2.07x10^-2 cm ^2)

*February 11, 2015*

**physics**

what is the electric force exerted on a test charge of 3.86 x 10^-5 C if it is placed in an electric field of magnitude 1.75 x 10^4 N/C ?

*February 11, 2015*

**Selam**

A real object is placed in front of a diverging lens, at a distance less than the focal length. When the object is moved slightly closer to the lens, which direction does the image move? away from the lens. doesn't move. closer to the lens. -- I know this is the answer But...

*January 21, 2015*

**tsion**

Determine whether each of the following statements is true or false. A concave mirror never forms an enlarged real image of a real object. >true A virtual image formed by a concave mirror is always smaller than the real object. >false A reduced image formed by a concave ...

*January 21, 2015*

**physics**

When a wave crosses a boundary between a thin and a thick rope, its frequency changes, but its wavelength and speed do not. True or false I think the answer is True

*November 23, 2014*

**PLEASE HELP PHYSICS**

Ok.

*November 23, 2014*

**projectives**

A cannon ball is fired horizontally with a velocity of 50m/s from the top of a cliff of 90mh. after how many seconds will it strike the plane at the foot of the cliff and at what distance at the foot of the cliff will it strike?

*November 9, 2014*

**Physics**

exam question

*November 3, 2014*

**n. i. o. s physics**

How would you design a black body?

*October 26, 2014*

**physics**

Two objects with masses 2.0 and 3.0 kg move toward each other, both with speeds V0 = 5.0 m/s. They collide head on and stick together. (a) Calculate their final velocity. (b) Calculate the amount of kinetic energy lost during the process. (c) Suppose the two masses approach ...

*September 6, 2014*

**physics**

How much heat is added to 10.5 g of ice at -20.0°C to convert it to steam at 123.5°C?

*May 26, 2014*

**help**

A sound wave travels at 343 m/s and a compression passes by every 12 ms. What is the wavelength of this sound?

*May 4, 2014*

**Physics**

A car with a mass of 900 kg moves along a road at a 89 km/hour at equal speed. On the road is a curve with a radius of 250. a) What is the force in the curve between the tires and the road if the road is horizontal? b) What inclination is the best for that car on the road...

*March 11, 2014*

**Physics**

i will not sure. This answer is write or wrong because this some is very difficult.sorry

*February 5, 2014*

**physics**

A toy rocket is launched at an initial velocity of 50 m/s at an angle of 75° with the horizontal. Write parametric equations to represent the path of the rocket. (A)x = 50t cos 75°y = 50t sin 75° – 4.9t2 (B)x = 50t cos 75°y = 50t sin 75° – 16t2

*January 29, 2014*

**PHYSICS PLEASE HELP**

A fire hose held near the ground shoots water at a speed of 6.5 m/s 1. At what angle(s) should the nozzle point in order that the water land 2.5 m away? -I believe the answer is 18,72 2. Sketch the trajectory for the 18; angle -Please give me exact (x,y coordinates) -I believe...

*January 26, 2014*

**Physics**

A pair of constant forces of magnitude F = 11.1 N is applied to opposite sides of the axle of a top, as shown in the figure. The diameter of the axle is d = 8.67 mm. The angle è, which has a value of 36.1°, describes the steepness of the top's sloping sides. The...

*December 10, 2013*

**Calculus Inegral**

integral of x/lnx

*November 14, 2013*

**physics**

A 0.0309-kilogram ball is stuffed into a spring gun and shot up into the air at some angle. The gun's spring has a force constant of 92.5 N/m and is initially compressed 0.138 m. When the ball reaches maximum height, it has a horizontal velocity with a speed of 2.23 m/s. ...

*November 11, 2013*

**Physics**

a 15-kg 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 just before the box starts to move

*October 30, 2013*

**Help!!**

An air-filled capacitor consists of two parallel plates, each with an area of 7.60 cm2, separated by a distance of 1.70 mm. (a) If a 16.0 V potential difference is applied to these plates, calculate the electric field between the plates. kV/m (b) What is the surface charge ...

*October 17, 2013*

**motion,physics**

Model rockets are lightweight rockets powered by very small engines. A typical model rocket has a mass of 5g.Similarly, a typical "class C" model rocket engine can produce a total impulse of 10 Newton-seconds. We usually launch model rockets vertically, but if I ...

*October 11, 2013*

**physics**

We are standing at a distance d=15 m away from a house. The house wall is h=6 m high and the roof has an inclination angle β=30 ∘. We throw a stone with initial speed v0=20 m/s at an angle α= 35 ∘. The gravitational acceleration is g=10 m/s2. (See figure...

*October 6, 2013*

**PHYSICS**

We are standing at a distance d=15 m away from a house. The house wall is h=6 m high and the roof has an inclination angle β=30 ∘. We throw a stone with initial speed v0=20 m/s at an angle α= 35 ∘. The gravitational acceleration is g=10 m/s2. (See figure...

*October 6, 2013*

**Physics**

no but how did you get it?

*October 6, 2013*

**Physics**

did you manage to solve it

*October 6, 2013*

**PHYSICS**

Two protons in a molecule are 3.80 multiplied by 10-10 m apart. Find the electrical force exerted by one proton on the other. Magnitude N (b) State how the magnitude of this force compares with the magnitude of the gravitational force exerted by one proton on the other. (...

*September 29, 2013*

**PHYSICS**

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C

*September 29, 2013*

**PHYSICS**

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C

*September 28, 2013*

**PHYSICS**

Two protons in a molecule are 3.80 multiplied by 10-10 m apart. Find the electrical force exerted by one proton on the other. Magnitude N (b) State how the magnitude of this force compares with the magnitude of the gravitational force exerted by one proton on the other. (...

*September 28, 2013*

**PHYSICS**

A rod 14.0 cm long is uniformly charged and has a total charge of -20.0 µC. Determine the magnitude and direction of the electric field along the axis of the rod at a point 36.0 cm from its center. N/C

*September 28, 2013*

**college physics**

Two protons in a molecule are 3.80 multiplied by 10-10 m apart. Find the electrical force exerted by one proton on the other. Magnitude N (b) State how the magnitude of this force compares with the magnitude of the gravitational force exerted by one proton on the other. (...

*September 28, 2013*

**physics**

A spectral line is emitted when an atom undergoes tranisition between two levels with a difference in energy of 2.4eV.What is the wavelength of the line (a)287nm(b)507angstrome units()377angstrome units(d)518nm

*September 22, 2013*

**physics**

A current flows in a wire of circular cross-section with the free electrons travelling with a mean drift velocity v. If an equal current flows in a wire of the same material but of twice the radius,what is the new mean drift velocity (a)v/4(b)v/2(c)2v(d)4v

*September 22, 2013*

**physics**

When a parachute opens, the air exerts a large drag force on it. This upward force is initially greater than the weight of the sky diver and thus slows him down. Suppose the weight of the sky diver is 905 N and the drag force has a magnitude of 1005 N. The mass of the sky ...

*August 21, 2013*

**Justin**

Four identical metallic spheres with charges of +2.2 µC, +8.2 µC, −4.6 µC, and −9.2 µC are placed on a piece of paper. The paper is lifted on all corners so that the spheres come into contact with each other simultaneously. The paper is then...

*August 19, 2013*

**Justin**

If 2.00 X 10^20 electrons move through a pocket calculator during a full day's operation, how many coulombs of charge moved through it?

*August 19, 2013*

**WIP**

A softball bat is rotating at 460 rotations per minute at contact with the ball. What is the angular velocity in radians?

*August 6, 2013*

**velocity**

what does velocity mean in physics?

*July 15, 2013*

**science**

a machine gun can fire 20 bullet persecond if speed of bullet is 100m/s and if each bullet weight 100grams calcuate force required to hold the gun in its position

*June 30, 2013*

**sam**

How much do you do if you push a garbage can with a force of 30N while sliding it 4 meters down the hall?

*May 29, 2013*

**Sam**

Is work being done by an ocean wave as ;it hits a dock with a force of 1000N?

*May 29, 2013*

**Physics**

Any one please ans this answer. The circuit below consists of three identical resistors each with resistance R=37 Ohm, two identical batteries with emfs E=25 V, and a capacitor with capacitance C=401 μF. The capacitor is initially uncharged at t = 0. (a) After a very very...

*May 22, 2013*

**Physics**

TA please give ans or formula for any ques tion you have got. 1c is 1.5*V V is volatage of the battery.

*May 22, 2013*

**Physics**

GR my values for Ques1 d part are V=25 C=401 R=37

*May 22, 2013*

**physics**

An alpha-particle collides with an oxygen nucleus which is initially at rest. The alpha-particle is scattered at an angle of 67.0 degrees from its initial direction of motion, and the oxygen nucleus recoils at an angle of 52.0 degrees on the other side of this initial ...

*April 24, 2013*

**physics**

An alpha-particle collides with an oxygen nucleus which is initially at rest. The alpha-particle is scattered at an angle of 67.0 degrees from its initial direction of motion, and the oxygen nucleus recoils at an angle of 52.0 degrees on the other side of this initial ...

*April 24, 2013*

**k**

Two wires parallel to each other and separated by a distance d carry different currents; they exert a force with magnitude F on each other. (a) The wires carry current in opposite directions. If the current carried by both wires is divided by five and the distance between the ...

*April 15, 2013*

**physics**

A roller-coaster car has a mass of 1100 kg when fully loaded with passengers. As the car passes over the top of a circular hill of radius 20 m, its speed is not changing. (a) At the top of the hill, what is the normal force (using the negative sign for the downward direction) ...

*March 9, 2013*

**Physics**

A uniform ladder weighing 197 N is leaning against a wall. The ladder slips when θ = 63.0°. Assuming that the coefficients of static friction at the wall and the ground are the same, obtain a value for µs.

*February 15, 2013*

**Ronit**

What is the current through a wire if 240 coulombs of charge pass through the wire in 2.0 minutes?

*February 10, 2013*

**Physics question**

A rope suspended from a ceiling supports an object of weight W at its opposite end. Another rope tied to the first at the middle is pulled horizontally with a force of 30N.the junction P of the rope is in equilibrum. Calculate the weight W and the tens.

*February 8, 2013*

**Physics question**

A boy intend to move an mkg crate across the floor by applying a constant force p newton on it.the coeficient of friction between the floor and crate is ü.which of these is the best option for his task?

*February 8, 2013*

**Science**

A 6 kg grinding wheel of radius 0.2 m rotates at a constant rotational frequency of 4 rad/s when an object makes contact with the outer edge of the wheel. Friction causes the wheel to stop in 2 seconds. What is the average torque on the wheel by the frictional force?

*February 5, 2013*