Earth rotates or spins on its axis once each day and revolves around the Sun once every year
Answer:
(c) 8240 kN
Resultant hydrostatic force F = 8240 kN
Explanation:
Force can be expressed as;
F = ma
F = mg ......1
Where,
F = force
m = mass
a = acceleration
g = acceleration due to gravity
And we know that mass of an object is the product of
Density and Volume
m = pV
And volume V = area × height = Ah
m = pAh .....2
Substituting m into equation 1
F = pAhg = pghA ......3
Given;
Density of water p = 1000kg/m^3
g = 9.81m/s^2
Area A = 20m × 12m = 240m^2
h = depth/2 = 7/2 = 3.5m
Substituting the values into equation 3, we have;
F = 1000×9.81×3.5×240
F = 8240400 N
Resultant hydrostatic force F = 8240 kN
The kinetic energy at the bottom of the swing is also 918 J.
Assume the origin of the coordinate system to be at the lowest point of the pendulum's swing. A pendulum, when raised to the highest point has potential energy since it is raised to a height h above the origin. At the highest point, the pendulum's velocity becomes zero, hence it has no kinetic energy. Its energy at the highest point is wholly potential.
When the pendulum swings down from its highest position, it gains velocity. Hence a part of its potential energy begins to convert itself into kinetic energy. If no dissipative forces such as air resistance exist, then, the law of conservation of energy can be applied to the swing.
Under the action of conservative forces, the total mechanical energy of a system remains constant.This means that the sum of the potential and kinetic energies of a body remains constant.
When the pendulum reaches the lowest point of its swing, it is at the origin of the chosen coordinate system. Its vertical displacement from the origin is zero, hence its potential energy with respect to the origin is zero. Therefore the entire potential energy of 918 J should have been converted into kinetic energy, according to the law of conservation of energy.
Thus, the kinetic energy of the pendulum at the lowest point of its swing is equal to the potential energy it had at its highest point, which is equal to <u>918 J.</u>
Iron is considered a micro-nutrient because only small amounts are required to aid in normal plant growth. ... Plants can suffer iron deficiency with symptoms of chlorosis and stunted growth, but plants can also take in too much iron, especially under certain growing conditions.
Answer:
3. 9600m/s
4. 2.5m/s
Explanation:
To find the final velocity of the object which accelerates at 40m/s/s for four minutes, we first need to convert the 4 minutes to seconds. There are 60 seconds in a minute so 4 minutes is equal to 4x60 = 240 seconds.
To calculate the final velocity we just multiply the acceleration rate by the time, so 40x240=9,600 m/s
The final velocity of the object would be 9600m/s.
If an object's final velocity was 115m/s after 45 seconds then we need to find out how much it accelerated in that 45 seconds to find the starting velocity. 45x2.5=112.5 It increased in speed by 112.5m/s over 45 seconds, so its initial speed was 112.5m/s slower than its final speed. 115-112.5=2.5, the object's starting velocity was 2.5m/s.
Hope this helped!