A single prolonged blast emitted by a boat using an efficient sound producing devices indicates that the boat is leaving the dock. It may also be used to indicate that the boat is moving and for alarming other vessels, but in this case, one prolonged blast is followed by two short blasts, in two minutes of time.
The principle of conservation of energy states that energy can neither be created nor destroyed, but can be changed from one form to another. The law of inertia on the other hand states that a body remains at a state of rest or motion on a straight line unless compelled by an external force. So i think that the answer is B, which is FALSE because the question is more related to the law of inertia(Newtons first law) than to the law of conservation of energy. Hope i helped.
Answer:
<h2>C</h2>
Explanation:
2.0 × 10^3 is the correct form for writing any term in scientific notation form.
Comment for understanding anything.
Answer: (b)
Explanation:
Given
Mass of box 
Applied force 
Friction force 
Box travels a distance of 
time taken 
Net unbalanced force 
Work done by the unbalanced force
Power developed by unbalanced force
Thus, option (b) is correct.
Answer:
Photoelectric effect, phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation.
Explanation:
The effect is often defined as the ejection of electrons from a metal plate when light falls on it. In a broader definition, the radiant energy may be infrared, visible, or ultraviolet light, X-rays, or gamma rays; the material may be a solid, liquid, or gas; and the released particles may be ions (electrically charged atoms or molecules) as well as electrons. The phenomenon was fundamentally significant in the development of modern physics because of the puzzling questions it raised about the nature of light—particle versus wavelike behaviour—that were finally resolved by Albert Einstein in 1905. The effect remains important for research in areas from materials science to astrophysics, as well as forming the basis for a variety of useful devices.
