Model a cancer cell as a circular disk 5.0 um in diameter, and let the light pulse last for 4.0 ns with a power of 2.0 × 10¹2 W. Assume that the energy is spread uniformly over the face of one cancer cell for each pulse. a. How much energy is given to the cell during this pulse? Show your calculation. b. What is the intensity (in W/m²) delivered to the cell? Show your calculation. c. What are the maximum values of the electric and magnetic fields in the pulse? Show your calculation, and don't forget units!

A laser emits a cylindrical beam of light 3.8 mm in diameter. The average power of the laser is 3.0 mW. The laser shines its light on a perfectly absorbing surface. Part A How much energy does the surface receive in 15 s ? Express your answer using two significant figures. —| ΑΣΦ E = Submit Part B What is the radiation pressure exerted by the beam? Express your answer using two significant figures. VE ΑΣΦ pressure av Request Answer Submit = Request Answer ? mJ ? μРа

The maximum strength of the magnetic field of an EM wave is 3.3×10^−6 T.   a. What is the maximum strength of the wave’s electric field? b. What is the average value of the E field? c. What is the average intensity of the EM wave?   PLEASE SHOW ALL WORK!! Thank you!!

Part C You are waiting for a pot of water to boil onthe stove. Your thermometer states that the temperature is 329.15 K (56 ° C). What is the frequency with the most intense radiation from the pot? O 3.41x1012 Hz O 1.55x10-5 Hz O 5.88x1010 O 1.94x1013 Hz O 5.17x10-14 Hz Submit Request Answer Part D In order to decrease the energy of a photon, you would need to O decrease its wavelength. O increase its wavelength. O decrease its speed. O increase its speed. Submit Request Answer

Part A You've recently read about a chemical laser that generates a 20.0-cm-diameter, 24.0 MW laser beam. One day, after physics class, you start to wonder if you could use the radiation pressure from this laser beam to launch small payloads into orbit. To see if this might be feasible, you do a quick calculation of the acceleration of a 20.0-cm- What speed would such a block have if pushed horizontally 95.0 m along a frictionless track by such a laser? Express your answer with the appropriate units. diameter, 98.0 kg, perfectly absorbing block. HA ? Value Units

He-Ne (Helium-Neon) lasers are often used in physics demonstrations. Mine is labelled as about 5 mW and 650 nm. Let's approximate that the light is spread over a cylindrical beam about 1 mm in diameter. a. What's the intensity of the beam (approximately)? b. What are the maximum electric and magnetic field values? What are the average values? Explain briefly why those are different. c. What's the average energy density of the beam? d. What's the frequency of the EM wave?

A 50 g horizontal metal bar, 15-cm-long, is free to slide up and down between two tall, vertical metal rods that are 15 cm apart. A 5.5×10-2 T magnetic field is directed perpendicular to the plane of the rods. The bar is raised to near the top of the rods, and a 1.2 resistor is connected across the two rods at the top. Then the bar is dropped. Part A What is the terminal speed at which the bar falls? Assume the bar remains horizontal and in contact with the rods at all times. Express your answer in meters per second. 跖 ΑΣΦ ? v = Submit Request Answer m/s

A laser has a power of 22.2 W and a beam radius of 0.478 mm. (a).Find.the.intensity of the laser. Enter a number. y defined? What factors affect the intensity of a beam of light? W/m (b) Suppose you were floating in space and pointed the laser beam away from you. What would your acceleration be? Assume your total mass, including equipment, is 74.8 kg and that the force is directed through your center of mass. Hint: The change in momentum is the same as in the nonreflective case. We know that the acceleration of an object is given by Newton's second law. How do we determine the net force acting on the accelerating object in this case? m/s (c) Calculate your acceleration if it were due to the gravity of a space station with mass 1.06 x 10° kg and center of mass 117.1 m away. m/s2 (d) Calculate the peak electric and magnetic fields of the laser. E max N/C B max %3D If you were planning to use your laser welding torch as a thruster to get you back to the station, don't bother because the…

É=-V ¢ where is the electric potential. One of Maxwell's Equations for EM is VE where p is the charge density. O Combine these two equations to get an expression for the dependence of ø on p.