<span>Mass of rock 1 is m1 = 10 kg Mass of rock 2 is m2 = 20 kg 10-kg rock takes T (the same time ) to reach the ground as similar to 20-kg rock that takes time T to reach the ground. If no air resistance is present, the rate of descent depends only on how far the object has fallen, no matter how heavy the object is. This means that two objects will reach the ground at the same time if they are dropped simultaneously from the same height. This statement follows from the law of conservation of energy and has been demonstrated experimentally by dropping a feather and a lead ball in an airless tube.
When air resistance plays a role, the shape of the object becomes important. THUS 10-KG & 20-KG ROCK reaches the ground in T-time</span>
Answer:
c. Both signals are simultaneous.
Explanation:
The speed of light is the same in all frame of reference.
Since an observer inside the ship receives both signals at the same time, then the signals from both flashlight are simultaneously.
Factors affecting friction
The intensity of friction depends on following factors: i) The area involved in friction. ii) The pressure applied on the surfaces. Force = Pressure ´ Area Frictional force will increase, if the area of contact will increase or if pressure applied on the surface increased.
Methods to reduce friction
i) Polish the contact surface. ii) Put oil or grease so that it fills in the small gaps of the flat parts. iii) Use ball bearings to reduce area of contact between rotating parts.
Lubrication
Following methods can be used to reduce friction: Oil is either thin or viscous. It depends upon SAE No. of oil. (SAE means Society of Automotive Engineers). If we use very viscous oil, it does not reach all the parts. Very thin oil will flows away easily and gets wasted. Grease is used in such cases. It is generally used around ball-bearing. Normal grease or oil is never used where there is high pressure, high temperature and high speed. Special lubricants are used in such cases. In cold season the oil becomes thick and in hot season it becomes thin. Therefore selection of lubrication also depends on the season. It is always advisable to refer operating manual of the equipment before selecting the lubricant.
Answer:
All music in the world, is form only two notes and those notes are described below in detailed explanation.
Explanation:
In the chromatic scale, there are basically seven central musical notes, designated A, B, C, D, E, F, and G. They individual express a separate pitch or frequency. For illustration, the "central" A note has a pitch of 450 Hz, and the "common" B note has a pitch of 495 Hz.
Varieties Of Musical Notes You Require To Understand
Semibreve (Whole Note)
Minim (Half Note)
Crotchet (Quarter Note)
1.28m/s the velocity is found by distance/time.