I think you should hold a stretch for 10-30 seconds
Answer:
atoms bond together and forms molecules
They both are mechanical waves.
Explanation:
Echolocation and ultrasounds are both mechanical waves that require a medium to trace through. They both process and transfer information through waves; the difference is that we humans cannot hear ultrasound waves.
Answer;
B. Fluorescent lamps operate at a higher temperature than incandescent lamps.
Explanation;
-A fluorescent lamp, is a type of electric light (lamp) that uses ultraviolet emitted by mercury vapor to excite a phosphor, which emits visible light.
-A fluorescent lamp produces less heat, thus, it is much more efficient. A fluorescent bulb can produce between 50 and 100 lumens per watt. This makes fluorescent bulbs four to six times more efficient than incandescent bulbs.
-Fluorescent lamps operate best around room temperature. At much lower or higher temperatures, efficacy decreases.
Answer:
A permanent magnet creates a magnetic field at all points in the surrounding region.
An electric current in a conductor creates a magnetic field at all points in the surrounding region.
A moving electric charge creates a magnetic field at all points in the surrounding region.
Explanation:
Magnet field is a region around the magnet in which the magnetic force can be experienced. A magnet has two poles: North pole and South pole. A Magnetic field originates from north pole and ends at south pole.
Magnets are of two types: Permanent magnet and temporary magnet.
A moving charge produces magnetic field. A stationary charge can not produce a magnetic field.
The rate of flowing charge constitutes an electric current. If the cardboard is placed around the current carrying conductor and the iron fillings spread around the cardboard then the iron nails get stick to it. It means that a current carrying conductor creates a magnetic field around it.
Therefore, the true statements from the given statements are as follows;
A permanent magnet creates a magnetic field at all points in the surrounding region.
An electric current in a conductor creates a magnetic field at all points in the surrounding region.
A moving electric charge creates a magnetic field at all points in the surrounding region.