Answer: The spring constant is K=392.4N/m
Explanation:
According to hook's law the applied force F will be directly proportional to the extension e produced provided the spring is not distorted
The force F=ke
Where k=spring constant
e= Extention produced
h=2m
Given that
e=20cm to meter 20/100= 0.2m
m=100g to kg m=100/1000= 0.1kg
But F=mg
Ignoring air resistance
assuming g=9.81m/s²
Since the compression causes the plastic ball to poses potential energy hence energy stored in the spring
E=1/2ke²=mgh
Substituting our values to find k
First we make k subject of formula
k=2mgh/e²
k=2*0.1*9.81*2/0.1²
K=3.921/0.01
K=392.4N/m
Express your answer to two significant figures and include the appropriate units.
The minimum speed with which the captain Sam Brady of the US continental army had to run off the edge of the cliff to make it safely to the far side of the river is or or or .
Further explanation:
As Captain Sam Brady jumps from the cliff, he moves in two dimension under the action of gravity.
Given:
The height of free fall of the captain Brady is or .
The horizontal distance moved by the captain Brady is or .
Concept:
The time required to free fall of a body can be calculated by using the expression given below.
……. (1)
The displacement is considered negative because the captain is moving in vertically downward direction.
Here, is the distance covered by the body in free fall, is the initial velocity of the object, is the acceleration due to gravity and is the time taken in free fall of a body.
As the Caption jumps off the cliff, he has his velocity in the horizontal direction. The velocity of the captain in vertical direction is zero.
Substitute for in the equation (1) .
Rearrange the above expression for .
…… (2)
Converting acceleration due to gravity in .
Substitute for and for in equation (2) .
Therefore, the time taken by captain to free fall a height is .
In the same time interval captain has to move in horizontal direction. The acceleration is zero in horizontal direction. So, the velocity will be constant throughout the motion in the horizontal direction.
The distance travelled by captain in the horizontal direction is given by,
Rearrange the above expression for .
…… (3)
Here, is the distance travelled in horizontal direction, is the velocity of the captain and is the time.
Substitute for and for in equation (3) .
Thus, the minimum speed with which the captain Sam Brady of the US continental army had to run off the edge of the cliff to make it safely to the far side of the river is or or or .
Learn more:
1. Energy density stored in capacitor brainly.com/question/9617400
2. Kinetic energy of the electrons brainly.com/question/9059731
3. Force applied by the car on truck brainly.com/question/2235246
Keywords:
Free fall, projectile, gravity, 1780, Brady’s, leap, Captain, Sam Brady, US, continental army, enemies, Ohio’s, Cuyahoga river, 22 ft, 6.7 m, 20 ft, 6.1 m, minimum speed, run off, edge, cliff, safely, far side, river, 19.71 ft/s, 6 m/s, 6 meter/s, 5.99 m/s, 599.8 cm/s.
Using the principles of projectile motion from Physics, Captain Sam Brady would need to run with an initial horizontal speed of approximately 19.64 ft/s to reach the far side of the river.
This problem can be solved using basic Physics, specifically projectile motion. Here, Captain Sam Brady had to run off the edge of the cliff to make it safely to the far side of the river which is 22 ft away while falling 20 ft down. We assume that he jumps horizontally (i.e., his initial vertical velocity is 0).
Firstly, we calculate the time for the vertical fall. Using the equation t = sqrt (2h/g) where h is height and g is the acceleration due to gravity (32.2 ft/s²), we get time t ≈ 1.12s (rounded to two significant figures).
Next, we can use this time to figure out his initial horizontal velocity needed. The equation v = d/t where v is velocity, d is distance, and t is time gives us v ≈ 19.64 ft/s (rounded to two significant figures).
So, Captain Sam Brady would need to run with an initial horizontal speed of approximately 19.64 ft/s to make it safely across the river.
#SPJ2
Answer:
Second projectile is 1.4 times faster than first projectile.
Explanation:
By linear momentum conservation
Pi = Pf
m x U + M x 0 = (m + M) x V
Now Since this projectile + pendulum system rises to height 'h', So using energy conservation:
KEi + PEi = KEf + PEf
PEi = 0, at reference point
KEf = 0, Speed of system zero at height 'h'
PEf = (m + M) g h
So,
So from above value of V
Initial velocity of projectile =U
Now Since mass of projectile and pendulum are constant, So Initial velocity of projectile is proportional to the square root of height swung by pendulum.
Which means
U₂ = 1.41 U₁
Therefore we can say that ,Second projectile is 1.4 times faster than first projectile.
In a ballistic pendulum experiment, if the pendulum swings twice as high with the second projectile as with the first, the speed of the second projectile must have been twice the speed of the first projectile.
In a ballistic pendulum experiment, the relation between speed of the particle and maximum height achieved by the pendulum relies on the law of conservation of energy. The kinetic energy of projectile (which is proportional to the square of the speed) gets converted into potential energy of the pendulum and hence the square of the speed of the particle is directly proportional to the maximum height achieved by the pendulum.
Given that the second projectile causes the pendulum to swing twice as high, the initial kinetic energy of the second projectile (and hence the square of its speed) must be four times that of the first. Thus, the speed of the second projectile must have been twice the speed of the first projectile, because the square root of 4 is 2.
#SPJ11
Directly proportional
wave energy
solar energy
Answer:
all the options listed are renewable sources of energy
Explanation:
renewable sources of energy are energy sources that are easily replenished naturally such as solar energy, wind energy , wave energy even energy from rain. These sources are usually environmental friendly that non renewable energy sources
non renewable energy however, are sources of energy that will eventually run out. examples are coal, crude oil, natural gas, nuclear energy. these sources mostly pose a high risk to the environment when being used.
hope this is quite helpful?