Answer;
D) one moving pulley attached to the object that is being lifted
Explanation;
-Pulleys are powerful simple machines. They can change the direction of a force, which can make it much easier for us to move something.
-A fixed pulley consists of a wheel fixed to a shaft and is used in conjunction with a belt to transfer energy to another fixed pulley. A movable pulley consists of a shell, a movable wheel and a rope. Movable pulleys are also know as block and tackle.
-One moving pulley attached to the object that is being lifted decreases the amount of effort force needed to lift an object.
Answer:
30 m³
Explanation:
Parameters given:
Initial volume of helium, V1 = 5 m³
Initial pressure in balloon, P1 = 30 kPa
Final pressure, P2 = 5 kPa
To find the volume of the balloon at that volume, we apply Boyle's law.
It states that at constant temperature, the pressure of a gas is inversely proportional to the volume of the gas.
Mathematically:
P = k / V
Where k = constant of proportionality
This implies that:
P * V = k
This means that if the pressure or volume of the gas changes at the same temperature, the product of the pressure and volume would be the same:
Hence:
P1 * V1 = P2 * V2
Hence, to find the final volume:
30 * 5 = 5 * V2
=> V2 = (30 * 5) / 5
V2 = 30 m³
The volume of the gas when the pressure is 5 kPa is 30 m³.
With what velocity does it hit the ground?
The acceleration of gravity is 9.8 m/s
Using the principles of free fall motion, it can be determined that a tennis ball dropped from a height of 1.16 meters would hit the ground with a velocity of 4.8 m/s.
The objective here is to calculate the initial velocity of the tennis ball just before it hits the ground. This is a physics question related to free fall motion. We will use the equation of motion, v^2 = u^2 + 2as, where 'v' is the final velocity, 'u' is the initial velocity, 'a' is the acceleration, and 's' is the distance. In our case, the initial velocity (u) is 0 because the ball is dropped, not thrown downwards.
The acceleration (a) is the acceleration due to gravity, which is -9.8 m/s² (it's negative because it acts downwards). The distance (s) will be the drop height, which is -1.16 m (it's negative because we're considering downwards as negative direction). Therefore, the equation becomes (v)^2 = 0 + 2*(-9.8 m/s²)*(-1.16 m). Solving this we get v = √(2*9.8*1.16) m/s = 4.8 m/s. So, the tennis ball hits the ground with a velocity of 4.8 m/s.
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True or False
Answer:
True
Explanation:
The object is at rest, which means it's not moving, so there is no net force on it, according to Newton's First Law.
B. size.
C. location.
D. speed.
E. temperature.
The property that distinguishes the potential energy from kinetic energy are the shape and position of the object, letter C. Potential energy is directly proportional with mass times gravity times the height of the object at rest. On the other hand, kinetic energy is directly proportional with half of the square of the velocity times the mass of the object in motion.
Answer: The amount of heat required for this process is 172.5 kJ.