Because: Some of the work done by the machine is used to overcome the friction created by the use of the machine. ... Work output can never be greater than work input. Machines allow force to be applied over a greater distance, which means that less force will be needed for the same amount of work.
Answer:
34.51
Explanation:
k=1/2mv² is the kenetic energy equation to fill is in
k=[1/2(0.235)×50]²
Answer:
D) the second at the doorknob
Explanation:
The torque exerted by a force is given by:

where
F is the magnitude of the force
d is the distance between the point of application of the force and the centre of rotation
is the angle between the direction of the force and d
In this problem, we have:
- Two forces of equal magnitude F
- Both forces are perpendicular to the door, so 
- The first force is exerted at the midpoint of the door, while the 2nd force is applied at the doorknob. This means that d is the larger for the 2nd force
--> therefore, the 2nd force exerts a greater torque
Answer:
the current flowing in each is the same.
Explanation:
When resistors are connected in series, they are connected in the same branch of the circuit - this means that the same current flows through each resistor.
The other options listed are wrong because:
the same power is dissipated in each one --> false: the power dissipated in each resistor is
, where I is the current and R the resistance, so it depends on the value of the resistance
the potential difference across each is the same.-- > false: this is true in parallel circuits, not series circuits
the equivalent resistance of the circuit is less than that of the smallest resistor.--> false: the equivalent resistance of a series circuit is the sum of the individual resistances:
, so it is larger than the resistance of the smallest resistance
the equivalent resistance of the circuit is equal to the average of all the resistances. --> false: the equivalent resistance of a series circuit is the sum of the individual resistances:
, not the average