Answer:
It depends on how you use the spoon...
if you are keeping one end of the spoon and pressing other end, the force you provide is supported by the force due to gravity... Hence it is easy to open this way :)
F + G ... Where F is the force you provide and G is the force due to gravity.
Answer:
D, using a spring scale to exert a force on the block. Measure the acceleration of the block and the applied force
Explanation:
For this you would use the net force equation acceleration=net force * mass however you will want to isolate mass so it would be acceleration/ net force to get mass. Then process of elimination comes to play.
Answer:
d. The ideal diode acts as a short circuit for forward currents and as an open circuit with reverse voltage applied.
Explanation:
Ideal diode acts like an ideal conductor. In case of forward voltage it acts like an ideal conductor. However when it is reverse biased then it behaves like an ideal insulator. You can understand it bu considering a switch. When the voltage is forward then ideal diode acts like a closed switch. When the voltage is reverse biased then ideal diode behaves like an open switch.
That is why we can say that the ideal diode acts as a short circuit (higher conduction) for forward currents and as an open circuit ( zero conduction) with reverse voltage applied.