# Homework Help: Science: Physics

## Recent Homework Questions About Physics

physics
What is the initial angle 0f projection of a projectile for which the range and the maximum height are equal?

physics
A particle (p) moves along the curved surface (s). Show that p will remain in contact with s provided that at all times its speed v≥√rgcosteta.

physics
The initial velocity of a projectile is 12i+13j in m\s. What is the displacement of a projectile at 0.25 seconds later?

physics
When I was traveling at 18m/s with my bike I approach traffic lights when I was 30m far from them they turned red and it took me to recognize and react by applying breaks then I decelerated to 4.6m/s2. How will I go and in which side of the traffic lights?

physics
Find the limiting velocity of a rain drop assuming diameter of 5.0×10^-4m.The density of air relative to water is 1.3×10^-3

Physics
the engineer of a passenger train traveling at 100 ft/sec sights a freight train whose caboose is 600 ft ahead of the same track. The freight train is traveling in the same direction as the passenger train with a velocity of 30 ft/sec. The engineer of the passenger train ...

AP Physics 1
A 1400 kg car is moving westward with a speed of 12 m/s, and a 3600 kg truck is traveling east with a speed of 27 m/s. Find the velocity of the center of mass of the system. Answer in units of m/sˆ

Physics
These are Thermodynamics questions: There is a 7 kg piece of aluminum at 80°C placed in a 3 kg water at 20°C what is the final temperature? There is a piece of aluminum at 90°C placed in 2 kg of water at 35°C how much energy is transferred if the final temperature is 45? ...

physics
a skateboarder with mass 75 kg is riding their skateboard of mass 8 kg at 1.5 m/s. If they decide to jump off sp that their body has no horizontal movement in the air before landing, how fast must the skateboard be moving after they separate

physics
A car, starting from rest, accelerates in the +x direction as in the figure. It has a mass of 1.10 × 103 kg and maintains an acceleration of +4.40 m/s2 for 2.60 s. Assume that a single horizontal force (not shown) accelerates the vehicle. Determine the average power generated...

physics
A 45-kg girl is bouncing on a trampoline. During a certain interval after leaving the surface of the trampoline, her kinetic energy decreases to 210 J from 400 J. How high does she rise during this interval? Neglect air resistance.

physics
A 64.2-kg skateboarder starts out with a speed of 2.21 m/s. He does 98.0 J of work on himself by pushing with his feet against the ground. In addition, friction does -276 J of work on him. In both cases, the forces doing the work are non-conservative. The final speed of the ...

Physics
You and another person go to the museum and decide to take a look at an exhibit that has a bike with an attached heating coil/generator. The coil is placed in a tank of water at 20 deg C. Peddling makes the coil increase the energy of the water. The goal is to make the water ...

physics
What mass of ice at -14°C will be needed to cool 200cm³ of an orange drink(essentially water) from 25°C to 10°C?

Physics
pressure of a fluid. calculate the a.) absolute pressure b.) gauge pressure at an ocean depth of 1000m. Assume the density of a sea water is 1024 kg cubic meter and that the air above exerts a pressure of 101.3kPa

physics
A simple U tube contains mrecury. When 13.6cm of water is poured in one arm caculate the rise of mercury in the other arm

physics
A man is standing on a platform that is connected to a pulley arrangement, as the drawing shows. By pulling upward on the rope with a force   the man can raise the platform and himself. The total mass of the man plus the platform is 121 kg. What pulling force should the man ...

physics
Force F1 acts on a particle and does work W1. Force F2 acts simultaneously on the particle and does work W2. The speed of the particle does not change. Which one of the following must be true? W1 is zero, and W2 is positive W1 = - W2 W1 is positive, and W2 is positive W1 is ...

physics
In which one of the following circumstances does the principle of conservation of mechanical energy apply, even though a nonconservative force acts on the moving object? The nonconservative force has a component that points opposite to the displacement of the object. The ...

physics
A 64.2-kg skateboarder starts out with a speed of 2.21 m/s. He does 98.0 J of work on himself by pushing with his feet against the ground. In addition, friction does -276 J of work on him. In both cases, the forces doing the work are non-conservative. The final speed of the ...

College Physics
A 0.697-kg basketball is dropped out of a window that is 6.98 m above the ground. The ball is caught by a person whose hands are 1.73 m above the ground. (a) How much work is done on the ball by its weight? What is the gravitational potential energy of the basketball, relative...

physics
Juggles the clown stands on one end of a teeter-totter at rest on the ground. Bangles the clown jumps off a platform 2.5 m above the ground and lands on the other end of the teeter-totter, launching Juggles into the air. Juggles rises to a height of 3.7 m above the ground, at ...

physics
A 89.7-kg skier rides a 3040-m-long lift to the top of a mountain. The lift makes an angle of 14.3 ° with the horizontal. What is the change in the skier's gravitational potential energy?

Physics
A 400g soccer ball is moving through the air at 3.57m/s [64.8°W of N] horizontally at the top of its flight. If at that instant, the soccer ball is struck by a 450g crocket ball moving at 5.46m/s [N], and the soccer ball flies off at 4.28m/s[22.4°W of N]. What will be the ...

Physics
An object is 10 mters long and has a weight of 125N. The weight of the object is determined by the expression, 250N= a10m+B kg/m. What are the units of a and B

Physics
It takes 226 kJ of work to accelerate a car from 23.3 m/s to 28.3 m/s. What is the car's mass?

physics
A fisherman is fishing from a bridge and is using a "43.0-N test line." In other words, the line will sustain a maximum force of 43.0 N without breaking. What is the weight of the heaviest fish that can be pulled up vertically, when the line is reeled in (a) at constant ...

physics
A 1450-kg submarine rises straight up towards the surface. Seawater exerts both an upward buoyant force of 16890 N on the submarine, as well as a downward resistive force of 1010 N. What is the submarine's acceleration?

Physics
What is the period of a wave that travels through a spring at 2.5 m/s and has a wavelength of 1.3 meters?

physics
A worker stands still on a roof sloped at an angle of 43° above the horizontal. He is prevented from slipping by a static frictional force of 520 N. Find the mass of the worker.

physics
Part (a) of the drawing shows a bucket of water suspended from the pulley of a well; the tension in the rope is 56.0 N. Part (b) shows the same bucket of water being pulled up from the well at a constant velocity. What is the tension in the rope in part (b)?

physics
The drawing shows a wire tooth brace used by orthodontists. The top-most tooth is protruding slightly, and the tension in the wire exerts two forces,  and , on this tooth in order to bring it back into alignment. If the forces have the same magnitude of 24.3 N, what is ...

physics
Three forces act on a moving object. One force has a magnitude of 76.5 N and is directed due north. Another has a magnitude of 46.3 N and is directed due west. What must be (a) the magnitude and (b) the direction of the third force, such that the object continues to move ...

College Physics
The space probe Deep Space 1 was launched on October 24, 1998. Its mass was 474 kg. The goal of the mission was to test a new kind of engine called an ion propulsion drive. This engine generated only a weak thrust, but it could do so over long periods of time with the ...

Physics
A Man Of Mass 80kg Carry A Load Of Bricks Of 20kg Up A Vertical Of Length 6m Calculate The Workdone

Physics
A Man Of Mass 80kg Carry A Load Of Bricks Of 20kg Up A Vertical Of Length 6m Calculate The Workdone.

Physics
A ball is allowed to fall freely from certain heightn. What distance it covers in 1st second?

physics
A body of mass 10 kg is attached to a wire 30 cm long. Area of cross section of the wire is 10 raise to power -6 metre square. It's breaking stress is 4.8×10 raise to power 7 N/metre square. Find maximum angular velocity with which it can be rotated in the horizontal circle?

Physics
Two blocks at rest on a frictionless inclined surface with mass of 3kg on a side inclined at 42° to the horizontal and mass 4.8kg a side inclined at 30° to the horizonal. if the two bodies are attached together by an extensible string passed through a pulley. A) Determine ...

Physics
Two forces are applied to a box on a frictionless surface. One force is 40 N [S]. The second force is 70 N [N30ºW]. What is the overall net force? a) 40.6 N [S59.5ºE] b) 110 N c) 40.6 N [N59.5ºW] d) 40.6 N [S30.5ºW]

Physics
An electric heater raises the temperature of 120g of water in a thin light vessel through 10K in 2mins, when placed in 70g of water contained in a metal vessel of mass 0.55kg the temperature rises through 9K in the same time. Calculate from the above: a)the heat supplied in ...

Physics
what mass of ice at -14'c will be needed to cool 200cm3 of an orange drink (essentially water) from 25'c to 10'c! (specific latent heat of fusion of ice =336000) (specific heat capacity of ice = 2100) (specific heat capacity of water = 4200)

Physics
calculate the specific heat capacity of the materials for which the heat supply, mass, and temperature rises are given below: i)25200J, 0.3Kg,20K ii)8000J, 500g, from 20'C to 60'C iii)9450J, 150g, from 15'C to 45'C

physics
an electric heater raises the temperature of 120g of water in a thin light vessel through 10K in 2mins, when placed in 70g of water contained in a metal vessel of mass 0.55kg the temperature rises through 9K in the same time. Calculate from the above: a)the heat supplied in ...

physics
calculate the specific heat capacity of the materials for which the heat supply, mass, and temperature rises are given below: i)25200J, 0.3Kg ii)8000J, 500g, from 20'C to 60'C iii)9450J, 150g, from 15'C to 45'C

physics
150g of ice at 0'c is mixed with 300g of water at 50'c. calculate the temperature of a mixture

physics
1) what mass of ice at -14'c will be needed to cool 200cm3 of an orange drink (essentially water) from 25'c to 10'c! (specific latent heat of fusion of ice =336000) (specific heat capacity of ice = 2100) (specific heat capacity of water = 4200)

Physics
An airplane travelling north at 400 m/s is accelerated due east at a rate of 50m/s^2 for 6 seconds. If the effects of air resistance and gravity are ignored, what is the final speed of the plane? My working: v=vo+at where a=50m/s Vo = 400 m/s t = 6s thus: Vo=400+50(6) =700m/s ...

Physics
Can someone please tell me how to derive this: its supposed to be projectile motion with spring x = Sqrt (dx*g*1/2*m) +(mgh sin2theta) ---------------------------- (1/2)(k)(sin2theta) all i got is r =v^2sin2theta / g x is displacement of elastic plz help

physics
Water is flowing in a pipe with a circular cross-section area ,and at all point the water completely fills the pipe.At point 1 ,the cross sectiona are of pipe is 0.070 meter square and the fluid velocity is 3.50 meter per second. a.) what is the fluid speed at point in the ...

pure physics
a stone weighs 0.25N in air and o.20N when completely immersed in water. what is the the up thrust on the stone?

physics`
which has more momentum: a snail moving at .001m/s or a 2-ton boulder resting on the ground? why?

Physics
The man pushes/pulls with a force of 200N. The child and the slide combo has a mass of 30 kg and coefficient of friction is 0.15. The angle between the slide and the ground is 30 degrees. Find the acceleration of the child and what is the frictional forces opposing his efforts

Physics
Can someone please tell me how to derive this: its supposed to be projectile motion with spring x = Sqrt (dx*g*1/2*m) +(mgh sin2theta) ---------------------------- (1/2)(k)(sin2theta) all i got is r =v^2sin2theta / g x is displacement of elastic plz help

Physics
An impulse of 25 N*s is exerted on a 0.25 kg baseball traveling 40 m/s west. What is the velocity of the baseball after it has been hit?

Physics
A ball with mass m=1kg and speed vo=5m/sec elastically collides with a stationary, identical ball (all resting on a frictionless surface so gravity is irrelevant). A student measures the top ball emerging from the collision at at speed vt=4m/sec at an angle ϴt ≈ 37°. a) ...

Physics
A car moving at 60 km/h skids 13 m with locked brakes. How far will the car skid with locked brakes at 180 km/h?

Physics
A great white shark of mass m1, coasting through the water in a nearly frictionless way at speed v1 engulfs a tuna of mass m2=0.10 m1 traveling in the same direction at speed v2 swallowing it in one bite. a) What is the speed of the shark after its meal? b) Did the shark gain...

Physics
the orbital period of the moon is 27.32 days. The international space station has an orbital period of 90 minutes. What is the mean distance between the center of the earth and the center of the international space station? moons orbital radius: 25,201

Physics
A bullet of mass m travelling at speed vo in the direction shohwn above strikes a block of mass M and embeds itself in it. The block is sitting on the edge of a frictionless table of height H and is knocked off of the table by the collision. a) What is the speed vb of the ...

Physics
A hammer of mass m falls from rest off of a roof and drops a height H onto your head. a) Assuming that the tool is in actual contact with your head for a time △t before it stops and slides off, what is the algebraic expression for the average force it exerts on your skull ...

Math, Physics
Calculate Earth's gravitational force on the ISS astronauts while orbiting at an altitude of 401.5 km above Earth’s surface.

physics
A boy lining a railway bridge 49ft. high, sees a train uproaching with uniform speed and attempt to drop a stone down to railway. He releases the stone when engine is 80ft. away from the point below his position and sees the stone hits in the ground just 3 ft. in front of the ...

Physics
At what frequency would a capacitor of 2.5 microfarads used in a radio circuit have a reactance of 250 ohms

physics
Only two forces act on an object (mass=3.19 kg), as in the drawing. Find (a) the magnitude and (b) the direction (relative to the x axis) of the acceleration of the object.

physics
An apple crate with a weight of 225 N accelerates along a frictionless surface as the crate is pulled with a force of 14.5 N as shown in the drawing. What is the horizontal acceleration of the crate?

physics
A mountain climber, in the process of crossing between two cliffs by a rope, pauses to rest. She weighs 520 N. As the drawing shows, she is closer to the left cliff than to the right cliff, with the result that the tensions in the left and right sides of the rope are not the ...

physics
During a storm, a tree limb breaks off and comes to rest across a barbed wire fence at a point that is not in the middle between two fence posts. The limb exerts a downward force of 253 N on the wire. The left section of the wire makes an angle of 15.4° relative to the ...

physics
One block rests upon a horizontal surface. A second identical block rests upon the first one. The coefficient of static friction between the blocks is the same as the coefficient of static friction between the lower block and the horizontal surface. A horizontal force is ...

physics
Traveling at a speed of 18.0 m/s, the driver of an automobile suddenly locks the wheels by slamming on the brakes. The coefficient of kinetic friction between the tires and the road is 0.580. What is the speed of the automobile after 1.44 s have elapsed? Ignore the ...

physics
A person pushes on a 55-kg refrigerator with a horizontal force of -250 N; the minus sign indicates that the force points in the -x direction. The coefficient of static friction is 0.56. (a) If the refrigerator does not move, what are the magnitude and direction of the ...

physics
A car is traveling up a hill that is inclined at an angle θ above the horizontal. Determine the ratio of the magnitude of the normal force to the weight of the car when (a)  θ = 17o and (b)  θ = 30o

physics
when an apple falls from a tree, and strikes the ground without bouncing, what happens to its momentum?

Physics
A 100 grams mass of a substance has a volume of 150 centmetre cube.Calculate the relative density of the substanc. [density of water pw=1.0gcm^-3]

Physics
An alloy of iron and silver has a total mass of 30 grams and a volume of 20.4cm^-3.Calculate the mass of iron only and the volume of silver only. [Density of iron=1.62gcm^3 and density of silver=0.9gcm^3]

Physics
A piece of metal of volume 250 centimetre cube floats in water when 85 percent of its volume is under water.Calculate the upthrust on the metal. [pw=1.0gcm^-3]

Physics
An empty bottle weighs 20 grams and 60 grams when filled completely with water.What would the bottle weigh when filled completely with mercury. [pw=1.0gcm^-3,pm=1.6gcm^-3]

physics
when temperature increases from t to # t and the moment of inertia is increase from I to #I. the coefficent of linear expansion is alpha .THE RATIO OF #I\I IS

Physics
A ball thrown with a speed of 100m/s attains a height of 150m (take g=9.8 per second square). Calculate: 1. Time of flight 2. Angle of projection 3. Range

Physics
What is specific heat

Science(physics)
A boy while driving to his school covers at the average speed of 15km/h.On his return trip along the same route, covers at the average speed of 25km/h due to less traffic.What is the average speed for the whole trip

Physics
The engineer of a passenger train moving at 29.0 m/s sees a freight train 360.m ahead on the track moving at 6.00 m/s. The engineer takes 0.400 seconds to react, and then applies the brakes. At what rate must the passenger train then decelerate in order to avoid a collision? ...

Physics
A 55kg person pushes on the floor with 800 N of force for 0.25 seconds. How high do they jump off the ground? I know how to find acceleration but I can't find distance.

Physics
An alloy of iron and silver has a total mass of 30 grams and a volume of 20.4 centimetre cube Calculate the mass of iron only and the volume silver only Please help

Physics
A piece of metal of volume 250 cetimetre cube floats in water when 85 percent of it's volume is under water.Calculate the upthrust on the metal. 250*85=21250

Physics
An empty bottle weighs 20g and 60g when filled completely with water.What will it weigh when filled completely with mercury? 20÷60=0.3

Physics
A student eats a dinner containing 8.0x10 raised to power 6j of energy. He wishes to do an equivalent amount of work in a nearby gym by lifting a 60kg object. How many times must he raise the object to expand this much energy? Assume that he raises it a distance of 2.0m each ...

physics
a runner in marathon passes the 5 mile mark at 1 o'clock and the 20 mile mark at 3 o'clock .what is the runners average speed during this time period?

physics
A passengers jet flies from one airport to another 1,200 miles away in 2.5h .Find its average speed.

physics
How far does a car going 25 m/s travel in 5s ? How far would a jet going 250 m/s travel in 5s?

Physics
Find the specific heat of an unknown metal given this data: Mass of the metal = 120 g Temp of the metal = 220 degrees Mass of the water = 30 g Initial Temp of the water = 20 degrees Final Temp of the water = 85.6 degrees Specific Heat of the water = 4.186 J/gram C I get 0.51 J...

physics
ifv=(3i+4j+5k)m/s is the instantaneous velocity of a body mass 1.50kg calculate its K.E

physics
An ostrich with a mass of 139 kg is running to the right with a velocity of 17 m/s. Find the momentum of the ostrich. Answer in units of kg · m/s.

physics
A car is traveling up a hill that is inclined at an angle θ above the horizontal. Determine the ratio of the magnitude of the normal force to the weight of the car when (a)  θ = 17o and (b)  θ = 30o.

Physics
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Physics
A 70.0-kg astronaut pushes to the left on a spacecraft with a force   in "gravity-free" space. The spacecraft has a total mass of 1.0 × 104 kg. During the push, the astronaut accelerates to the right with an acceleration of 0.36 m/s2. Determine the magnitude of the ...

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 869 N and the drag force has a magnitude of 1096 N. The mass of the ...

physics
Two skaters, a man and a woman, are standing on ice. Neglect any friction between the skate blades and the ice. The mass of the man is 84 kg, and the mass of the woman is 49 kg. The woman pushes on the man with a force of 58 N due east. Determine the acceleration (...

physics
In a quarter-mile drag race, two cars start simultaneously from rest, and each accelerates at a constant rate until it either reaches its maximum speed or crosses the finish line. Car A has an acceleration of 11.0 m/s2 and a maximum speed of 110 m/s. Car B has an acceleration ...

physics
An electron is a subatomic particle (m = 9.11 x 10-31 kg) that is subject to electric forces. An electron moving in the +x direction accelerates from an initial velocity of +7.62 x 105 m/s to a final velocity of 2.56 x 106 m/s while traveling a distance of 0.0778 m. The ...