The best answer would be the 4th choice. "They help scientists explain concepts that are difficult to observe, this also covers the first answer which helps the scientist to answer complex questions. A scientific model is not used prove scientific laws as they may not always have all the data to prove so, instead it is used to allow them to explain better concepts revolving around science through research and may also allow them to predict results based on the accumulation of data and analyzing the trend of this resulting information.
Answer:
Graph B represents correct graph for velocity time
Explanation:
Initially the object is dropped under the influence of constant force due to gravity
So here we can say its acceleration is constant due to gravity
hence here the velocity will increase downwards due to gravity and it is given as
now when it enters into the pool an upward force of same magnitude will act on it
so net force on it is
so here we will have no acceleration and it will move with constant speed after that
so here correct graph is
Graph B
Answer: Frequency refers to the number of occurrences of a periodic event per time and is measured in cycles/second. In this case, there is 1 cycle per 2 seconds. So the frequency is 1 cycles/2 s = 0.5 Hz.
Answer: 5.8kg
Explanation:
F - mg sinΦ = ma
Given that
M=?
g= 9.8
Φ= 30
a= 2
F= 40 then
40 - 9.8 * m * sin 30 = 2 * m
40 = 2 * m + 9.8 * m * sin 30
40 = (2 + 9.8 * sin 30) m
m = 40 / (2 + 9.8 * 0.5)
m = 40 / (2 + 4.9)
m = 40 / 6.9
m = 5.797kg
m = 5.8kg
