Physical science is defined as the study of observable phenomena in the universe.<span>The main idea of physical science is known as the "scientific method". </span>
<span>This method states: </span>
<span>1. observe a "real" ( not imaginary ) phenomena. </span>
<span>2. make a hypothesis ( or theory / idea ) that EXPLAINS this phenomena. </span>
<span>3. conduct a real experiment to test this hypothesis. </span>
<span>4. confirm that the experiment validates the original hypothesis and if necessary amend the theory. </span>
<span>This method is responsible for virtually every scientific explanation of every kind. </span><span>It has worked so well that the very communication you are having with me is a result of the wonders of physical science. </span>
<span>Hope your question was answered :)</span>
The box is accelerated from rest to 4 m/s in a matter of 2.5 s, so its acceleration <em>a</em> is such that
4 m/s = <em>a</em> (2.5 s) → <em>a</em> = (4 m/s) / (2.5 s) = 1.6 m/s²
Then the force applied to the box has a magnitude <em>F</em> such that
<em>F</em> = (10 kg) (1.6 m/s²) = 16 N
<h2>What is an electric fuse?</h2><h3>
Answer: Electric fuse is a safety device used to limit the current in an electric circuit which melts and breaks the circuit whenever there is an excess flow of current through the circuit.</h3><h2>What is the working principle of electric fuse?</h2><h3>An electric fuse is based on the principle of heating effect of electric current. It is made up of thin metallic wire of non-combustible material. A fuse is always connected between the ends of the terminal in a series connection with the circuit.</h3>
Answer:
The time is 
Explanation:
Given that,
Number of energy level n= 1
Energy E₁=4 eV
We need to calculate the time period
Using formula of time period


Where, E = energy

h = Planck constant
Put the value into the formula



Hence, The time is 