When you're using a crowbar to lift a large rock, you are working against the force called


Gravity on Earth is what gives weight to all objects, it's defined as all things that have mass or energy are gravitated towards each other. Therefore when you're using a crowbar to lift a large rock, the weight is caused by
gravity.
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Primary Circular Reactions (1-4 months): This substage involves coordinating sensation and new schemas. For example, a child may suck his or her thumb by accident and then later intentionally repeat the action. These actions are repeated because the infant finds them pleasurable.
Nuclear fusion reactions convert protons into helium; thus, becoming the source of all energy radiated by the sun.
Answer: Option D
<u>Explanation:</u>
Nuclear fusion reaction is one among the two nuclear reactions in which the atoms nucleus interact with each other to produce the products. In nuclear fusion, two smaller atoms react together to form a new atom with bigger size.
So large amount of energy is required to start the nuclear fusion reaction. The fusion reactions mostly occurs in stars. The illumination in Stars even the Sun is due to nuclear fusion reaction occurring with the atoms present in them.
Mostly the energy radiated by Sun is due to the protons-protons chain reaction. In this chain reaction, the protons get converted into helium due to nuclear fusion reaction, thus becoming the source of all energy radiated by the Sun.
Explanation:
Given that,
Initial speed of the object, u = 1 m/s
Acceleration of the object, 
We need to find the time when the object comes at rest (v=0). Let it is given by :


t = 1 second
So, the object will comes to rest at 1 second. Hence, this is the required solution.
Answer:
The moment is 81.102 k N-m in clockwise.
Explanation:
Given that,
Force = 260 N
Side = 580 mm
Distance h = 370 mm
According to figure,
Position of each point



We need to calculate the position vector of AB


We need to calculate the unit vector along AB


We need to calculate the force acting along the edge


We need to calculate the net moment

Put the value into the formula




Put the value into the formula


Negative sign shows the moment is in clockwise.
Hence, The moment is 81.102 k N-m in clockwise.