Answer:
B. Thermal energy
E. Sound energy
Explanation:
Thermal and sound energy is kinetic energy.
Kinetic energy is the energy that results as a function of the motion of a body or the particles of the medium.
Sound energy is transmitted by the vibration of the particles in the air. The vibration leads to movement of the particles and hence, kinetic energy is produced.
Thermal energy originates as a result of the temperature differences in a body. This temperature difference leads to the increase in the kinetic energy of some particles which also causes vibration and motion of the particles.
It depends on the indicator, and the pH range over which it will experience a colour change. Some indicators will change colour<span> in an acidic solution, others will not. For example, blue litmus paper will turn red in an acidic solution, but red litmus paper will not change colour. The test would be inconclusive with red litmus paper, since it does not change colour in an acid and in a neutral solution.</span>
Answer:
1.3 × 10⁸ e⁻
Explanation:
When a honeybee flies through the air, it develops a charge of +20 pC = + 20 × 10⁻¹² C. This is a consequence of losing electrons (negative charges). The charge of 1 mole of electrons is 96468 C (Faraday's constant). The moles of electrons representing 20 pC are:
20 × 10⁻¹² C × (1 mol e⁻/ 96468 C) = 2.1 × 10⁻¹⁶ mol e⁻
1 mole of electrons has 6.02 × 10²³ electrons (Avogadro's number). The electrons is 2.1 × 10⁻¹⁶ moles of electrons are:
2.1 × 10⁻¹⁶ mol e⁻ × (6.02 × 10²³ e⁻/ 1 mol e⁻) = 1.3 × 10⁸ e⁻
Answer:
A. Normal force is always perpendicular to the area of contact between an object and support.
Explanation:
Normal force is defined as the contact force. If there is no contact between the surfaces, they cannot applies a force which is normal on each other. For e.g, the surfaces of a cubical box and the cart cannot applies a force of normal on each other because of no contact.
If, when there is a contact between two surfaces they applies a normal force on each other, and this force is perpendicular to the each other . This normal force is necessary to prevent object to penetrating into other.
Answer:
A or B depending on your precision
Explanation:
In real life, applying to solid will shrink it depending on the amount of pressure applied, but due to the strength of solid bonds, the volume change is often negligible in practical situation and would only be accounted under astronomically high pressure phenomena (eg. at Jupiter's core or near black hole).
In high school level, and for many applications, it is entirely viable to completely neglect the change in solid volume under pressure. Thus, A is a legitimate answer. However, bear in mind that <em>in theory</em> the volume still decreases by a very slight amount. So B is correct as well, theoretically. The most correct option depends on the precision you needed.
