If an object is not accelerating, how many
forces act on it?

If an object is not accelerating, no forces can act on it.  

•Energy or strength imparted on one object by another thing is termed as a force. The rate of change of velocity of an object with respect to time is termed acceleration.  

•In case, if no acceleration is there, then the object will move with the same velocity, and based on Newton's second law when no acceleration is there, and the body is moving at the same velocity then the force acting on the body will also be zero.  

•An object, which is decelerating or not accelerating has no forces acting on it.  

Thus, if an object is not accelerating, no forces act on it.

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If an object is not accelerating, then zero net forces act on the object.

Explanation:

As per Newton's second laws of motion, an object exhibiting acceleration is directly proportionate to the net forces act on the objects and inversely proportionate to the object's mass.

But object's mass cannot be zero, so if the acceleration is zero for an object, the total forces act on that object will be zero. And for zero net force to occur, two equal but opposite forces are enough to nullify the net force. Thus if an object does not accelerate, then zero net force acts on the object.

answer: the rock sample is a sedimentary rock.

explanation:

it is given that:

mass of rock sample, m = 2.7 g

volume of rock sample,

so, density of rock sample will be

since, the density of rock sample is . hence, the rock sample is a sedimentary rock, whose densities varies between .