Weight is

Options

A. measured by a spring balance
B. measured by a beam balance
C. measured in kg
D. a scalar quantity

Answer

### Step-by-Step Solution

**Step 1: Understanding Weight**
- Weight is defined as the force exerted by gravity on an object. It is the product of the mass of the object and the acceleration due to gravity (g). The formula for weight (W) is:
\[ W = m \cdot g \]
where \( m \) is the mass of the object and \( g \) is the acceleration due to gravity (approximately \( 9.81 \, \text{m/s}^2 \) on the surface of the Earth).

**Step 2: Measurement of Weight**
- Weight is commonly measured using a spring balance. A spring balance works on the principle of Hooke's law, where the extension of a spring is proportional to the weight of the object attached to it. Therefore, the statement that weight is measured by a spring balance is **true**.

**Step 3: Distinction Between Mass and Weight**
- Mass is a measure of the amount of matter in an object and is measured in kilograms (kg). In contrast, weight is a force and is measured in newtons (N). Therefore, the statement that weight is measured in kg is **false**; weight is measured in newtons.

**Step 4: Vector vs. Scalar Quantity**
- Weight is a vector quantity because it has both magnitude and direction (the direction is towards the center of the Earth). In contrast, mass is a scalar quantity, which means it only has magnitude and no direction. Therefore, the statement that weight is a scalar quantity is **false**; weight is a vector quantity.

**Step 5: Conclusion**
- Based on the analysis of the options provided:
- Option 1: True (Weight is measured by a spring balance)
- Option 2: False (Beam balance measures mass, not weight)
- Option 3: False (Weight is measured in newtons, not kilograms)
- Option 4: False (Weight is a vector quantity, not a scalar)

Thus, the correct answer is that weight is measured by a spring balance.