The official web site of the Nobel Prize explains that Marie Curie’s chemistry prize was partly for her discovery that the radioactivity of a substance is unaffected when it undergoes a chemical reaction. The discovery implied was that, Radioactivity involves Radioactivity involves only neutrons.
Explanation:
- The official web site of the Nobel Prize explains that Marie Curie’s chemistry prize was partly for her discovery that the radioactivity of a substance is unaffected when it undergoes a chemical reaction. The discovery implied was that, Radioactivity involves only neutrons.
- Marie Curie studied about the radiation of all compounds containing the known radioactive elements, including uranium and thorium, which she later discovered that they were radioactive.
- she discovered the following results,
- the exact measurement of the strength of the radiation from uranium;
- the intensity of the radiation was found to be proportional to the amount of uranium or thorium in the compound .
- the ability to emit radiation is not dependent on the arrangement of the atoms in a molecule;
- it must be linked to the interior of the atom itself which is a revolutionary discovery.
Answer:
150 million kilometres
Explanation:
The astronomical unit (symbol: au, or AU or AU) is a unit of length, roughly the distance from Earth to the Sun and equal to 150 million kilometres (93 million miles) or 8.3 light minutes.
The statement which best describes how light waves travel in an uniform medium is in straight lines. The correct answer will be A.
Answer:
a) v_average = 11 m / s, b) t = 0.0627 s
, c) F = 7.37 10⁵ N
, d) F / W = 35.8
Explanation:
a) truck speed can be found with kinematics
v² = v₀² - 2 a x
The fine speed zeroes them
a = v₀² / 2x
a = 22²/2 0.69
a = 350.72 m / s²
The average speed is
v_average = (v + v₀) / 2
v_average = (22 + 0) / 2
v_average = 11 m / s
b) The average time
v = v₀ - a t
t = v₀ / a
t = 22 / 350.72
t = 0.0627 s
c) The force can be found with Newton's second law
F = m a
F = 2100 350.72
F = 7.37 10⁵ N
.d) the ratio of this force to weight
F / W = 7.37 10⁵ / (2100 9.8)
F / W = 35.8
.e) Several approaches will be made:
- the resistance of air and tires is neglected
- It is despised that the force is not constant in time
- Depreciation of materials deformation during the crash
Answer:
0 m/s
Explanation:
Average velocity of an object is given by the net displacement divided by time taken. Displacement is equal to the shortest path covered by the object.
In this problem, a player runs the length of the 30-meter court and back. The player does this three times in 60 seconds.
As the player runs the court and returns to the original point. It would mean that the shortest path covered is 0.
Average velocity = displacement/time
v=0/30
v = 0 m/s
Hence, the correct option is (1).
