Answer;
-Single replacement
Explanation;
The reaction;
Cu(s) + 2AgNO3= Cu(NO3)2 + 2Ag , is an example of a single replacement reaction.
-It is a type of chemical reaction where an element reacts with a compound and takes the place of another element in that compound.
In the above reaction copper(Cu) takes the place of silver(Ag) in the salt AgNO3 to form Copper (ii) nitrate (CuNO3) and silver metal (Ag).
- Another example of a single replacement reaction occurs when potassium (K) reacts with water (H2O). A colorless solid compound named potassium hydroxide (KOH) forms, and hydrogen gas (H2) is set free.
Answer:
The correct option is (A).
Explanation:
When the temperature of the hot solid object increases then the radiation which emits from it gets shifted to smaller wavelength or higher frequencies. The hot appears red color.
The total energy emitted of a hot solid object is directly proportional to the fourth power of the temperature of the black body.
For example, when we switch on the light bulb, initially the radiation of the bulb appears dimmer. Then, it will become brighter. Then, it will turn yellow and then it becomes even white.
The color of the light emitted by a hot solid object depends on the temperature of the object.
Therefore, the correct option is (A).
Answer:
This equation is based on twin paradox - a phenomena where one of the twin travels to space at a speed close to speed of light and the other remains on earth. the twin from the space on return discovers that the one on earth age faster.
Solution:
= 10 years
v = 0.8c
c = speed of light in vacuum
The problem can be solved by time dilation equation:
(1)
where,
t = time observed from a different inertial frame
Now, using eqn (1), we get:

t = 16.67 years
The age of the twin on spaceship according to the one on earth = 25+16.67 =41.66 years
Answer:
15.6m/s
Completed Question;
For a short period of time, the frictional driving force acting on the wheels of the 2.5-Mg van is N= 600t^2 , where t is in seconds. If the van has a speed of 20 km/h when t = 0, determine its speed when t = 5
Explanation:
Mass m = 2500kg
Speed v1 = 20km/h = 20/3.6 m/s = 5.556 m/s
To determine speed v2;
Using the principle of momentum and impulse;
mv1 + ∫₀⁵ F dt = mv2
<span>a. A solid will gain kinetic energy and become a liquid.</span>