Figure P19.35a is a diagram of a device called a velocity selector, in which particles of a specific velocity pass through undeflected while those with greater or lesser velocities are deflected either upwards or downwards. An electric field is directed perpendicular to a magnetic field, producing an electric force and a magnetic force on the charged particle that can be equal in magnitude and opposite in direction (Fig. P19.35b) and hence cancel. Show that particles with a speed of v = E/B will pass through the velocity selector undeflected.

An alien from a planet in the galaxy M31 (Andromeda) has a ray gun that shoots protons at a speed of 2.0 × 10^5 m/s. Design a magnetic shield that will deflect the protons away from your body. A) Suppose that the magnetic field has horizontal direction and you want to deflect the beam through a path with radius R = 2.0 m as shown in (Figure 1). Find the field strength needed to achieve the desired deflection. The mass of a proton is 1.67× 10^−27 kg and its charge is 1.6× 10^−19 C. B) What is the direction of the magnetic field in the region defined in (Figure 1), that would cause the deflection shown for the proton beam? along the path of the proton beam into the page toward the center of the curved path out of the page C)What is the direction of the magnetic force in the region defined in (Figure 1), that would cause the deflection shown for the proton beam? along the path of the proton beam into the page toward the center of the curved path out of the page

A magnetic field has a magnitude of 0.0017 T, and an electric field has a magnitude of 4.7 x 103 N/C. Both fields point in the same direction. A positive 2.1-μC charge moves at a speed of 3.1 x 106 m/s in a direction that is perpendicular to both fields. Determine the magnitude of the net force that acts on the charge. B Number i 9 V 90° Units E

A proton is projected perpendicularly into a magnetic field that has a magnitude of 0.23 T. The field is then adjusted so that an electron will follow a circular path of the same radius when it is projected perpendicularly into the field with the same velocity that the proton had. What is the magnitude of the field used for the electron? Be=