Answer:
6.85 m/s
Explanation:
We can solve the problem by using the law of conservation of momentum.
In fact, since there are no external forces acting, the total momentum before and after must be conserved. So we can write:
where
is the initial mass of the car
is the initial speed of the car
is the mass of the car after the load of gravel is dropped
v2 is the final speed of the car
Solving for v2, we find
Answer:
C. Sports activity
Explanation:
A sport activity is a form of competitive physical activity in forms of games. They are normally organized for individuals to participate with the aim of improving physical abilities and skills, bring enjoyment to participants and act as a form of entertainment.
Remember the rule of thumb that every person learns in Elementary Science? You must do multiple experiments in order to get to a conclusion. In order for a conclusion to be valid you must test the conclusion multiple times. You wouldn't want a doctor to just test an aspirin 1 time on 1 patient and say yes it works correct? No, you would want him/her to test on multiple patients in multiple settings and conditions so that when you take an aspirin you know that it will work for what you are taking it for. So ..... with all that being said.....Your answer is (A). The results are more likely to have errors.
Answer:
1 kg
Explanation:
Applying,
Hook's law,
F = ke................. Equation 1
Where F = force, k = force constant of the spring, e = extension.
But from the question,
The weight of the bottle is the force acting on the spring scale
therefore,
mg = ke............ Equation 2
Where m = mass of the bottle, g = acceleration due to gravity.
make k the subject of the equation
k = mg/e............ Equation 3
Given: m = 0.5 kg, e = 1 cm = 0.01 m
Constant: g = 9.8 m/s²
k = (0.5×9.8)/0.01
k = 490 N/m
If the mass of the second bottle is weighed,
given: e = 2 cm = 0.02 m
subtitute into equation 1
m×9.8 = 490×0.02
9.8m = 9.8
m = 9.8/9.8
m = 1 kg.
Hence the mass of the second bottle is 1 kg
