Answer:
k = 26.25 N/m
Explanation:
given,
mass of the block= 0.450
distance of the block = + 0.240
acceleration = a_x = -14.0 m/s²
velocity = v_x = + 4 m/s
spring force constant (k) = ?
we know,
x = A cos (ωt - ∅).....(1)
v = - ω A cos (ωt - ∅)....(2)
a = ω²A cos (ωt - ∅).........(3)
now from equation (3)
k = 26.25 N/m
hence, spring force constant is equal to k = 26.25 N/m
Answer: Weight = 98.1N
Explanation:
Density of water = 1000 kg/m^3
Given that the Plastic foam is about 0.10 times as dense as water. That is,
Density of plastic foam = 0.1 × 1000 = 100kg/m^3
The volume V = 1 ×1×0.1 = 0.1 m^3
Density is the ratio of mass to volume
Density = mass/volume
Let us substitute for density and volume to get mass.
100 = M/0.1
Make M the subject of formula
M = 100 × 0.1 = 10 kg
Weight = mg
Where g = 9.81 m/s
Substitute the M and g into the formula
Weight = 10 × 9.81 = 98.1 N
Therefore, the weight of the brick is 98.1 N
Assuming 280 miles is the total distance travelled:
Let b = boat speed in still water
Let c = current speed.
For the downstream trip the speed is b + c. In 7 hours at the speed of (b + c) mph the boat travels 140 miles.
7(b + c) = 140 .............(1)
For the upstream trip the speed is b - c. In 14 hours at the speed of (b - c) mph the boat travels 140 miles.
14(b - c) = 140 ............(2)
The left hand sides of equations (1) and (2) are equal. Therefore we can write
7b + 7c = 14b - 14c ...........(3)
Rearranging equation (3) we get
21c = 7b
c = b/3 .......................(4)
The value for c obtained in equation (4) should now be substituted into equation (1) which can then be solved to find the value of b.
Answer: It would increase.
Explanation:
The equation for determining the force of the gravitational pull between any two objects is:
Where G is the universal gravitational constant, m1 is the mass of one body, m2 is the mass of the other body, and r^2 is the distance between the two objects' centers squared.
Assuming the Earth's mass but not its diameter increased, in the equation above m1 (the term usually indicative of the object of larger mass) would increase, while the r^2 would not.
Thus, it goes without saying that, with some simple reasoning about fractions, an increasing numerator over a constant denominator would result in a larger number to multiply by G, thus also meaning a larger gravitational strength between Earth and whatever other object is of interest.
A campfire being lighted and plants converting carbon-dioxide and water into glucose and oxygen are both forms of chemical change.
Therefore, the answer is:
B. Both are examples of chemical change.
