What is tension of a string that is holding up an object in water equal to?

the force pulling on the string.

Can Tension equal Apparent weight when a block is suspended in water?

yes. what else could it be?

To determine the tension of a string holding up an object in water, you need to consider the forces acting on the string and the object.

In this scenario, the object is partially or completely submerged in water, therefore, there are two main forces acting on it: the weight of the object (due to gravity) and the buoyant force.

The weight of the object is the downward force exerted on it due to gravity. It can be calculated using the formula:

Weight = mass * acceleration due to gravity

The buoyant force is the upward force exerted on the object by the water, which opposes its weight. It is equal to the weight of the water displaced by the submerged portion of the object. It can be calculated using Archimedes' principle:

Buoyant force = weight of displaced water

Now, let's consider the string. Since it is holding up the object, it must balance the downward weight force and the upward buoyant force. Therefore, the tension in the string is equal to the sum of these two forces.

Tension = weight + buoyant force

Keep in mind that the tension in the string may vary depending on the depth or the specific properties of the object and the water.