1. The value of voltage across the diode in figure given below is (a) Zero volt (b) 4 V (c) 8 V (d) Depends upon the value of R 2. The temperature co-efficient of an intrinsic semiconductor is (a) Zero (b) Positive (c) Negative (d) Like that of metals 3. A 4-pole, 1200 rpm DC […]
For rotary AC motors, asynchronous (induction) motors are more common than synchronous motors. But when it comes to linear motion, linear synchronous motors, abbreviated LSMs, are more common. The vast majority of LSMs I’ve seen have permanent magnets, so this article focuses exclusively on permanent magnet LSMs. Structure of Linear Synchronous Motors In general, linear
Linear motors move in a straight line with linear force and speed. Linear motion is needed in many types of systems, but linear motors aren’t commonly used by makers or professional engineers. That’s because these motors aren’t well-understood, there aren’t many manufacturers, and they’re expensive. For these reasons, designers frequently obtain linear motion by connecting
1. The value of current I flowing in the 1 ohm resistor in the circuit shown in the figure below will be (a) 10A (b) 6A (c) 5A (d) zero 2. In the figure shown below, if we connect a source of 2V, with internal resistance of 1 ohm at AA’ with positive terminal at
Introduction of microcontroller Microcontroller is a type of single-chip integrated circuit that contains one or more microprocessor cores, instruction sets, flash memory, RAM, EEPROM, external bus interfaces, and various digital/analog input/output ports. Its main function is to interact, control, monitor, and transfer data with peripheral devices based on programmed code, collect data from external signal
Microcontrollers: What They Are and How They Drive the Digital World Read More »
1. The Forth Military World Games were held in October, 2007 in India at (a) Hydrabad (b) Chennai (c) Ahmedaba (d) Lucknow 2. Who of the following received the Sanskriti Award for 2007 in the field of literature? (a) Jyotshna Kalita (b) K.A. Shaji (c) K.P. Reji (d) Bijayini Satpathy 3. The legislative Council in
1. The best conductor of heat among liquids is (a) water (b) mercury (c) ether (d) alcohol 2. The layer of the atmosphere which reflects ratio waves back to the earth is called (a) Stratosphere (b) Tropopause (c) Ionosphere (d) Troposphere 3. An object weigth maximum in (a) air (b) water (c) hydrogen (d) vacuum
This article focuses on a motor intended for motion control—the servomotor, or servo. Whereas stepper motors rotate through an angle and halt, many servo motors rotate continuously. Properly controlled, a servo can do everything a stepper can and more. In addition to setting the rotation angle, the controller can configure the servo’s rotational speed and
A stepper motor’s purpose is to rotate through a precise angle and halt. The speed and torque of the rotation are secondary concerns. As long as the stepper rotates through the exact angle and stops, its mission is accomplished. Each turn is called a step, and common step angles include 30°, 15°, 7.5°, 5°, 2.5°,
Stepper Motor Control Because VR steppers are so scarce, this article focuses on controlling PM and HY steppers, which are almost always two-phase motors. Some PM and HY steppers are bipolar and have four wires. Others are unipolar and have five or six wires. The terms bipolar and unipolar identify how the wires are connected