Introduction to Trigonometry for Calculating Forces in Trusses

The video tutorial covers the basics of calculating forces in trusses, starting with a review of the Pythagorean theorem and moving into trigonometry concepts like SOHCAHTOA. It explains how to use trigonometry to find missing side lengths and angles in right triangles. The tutorial also discusses how to split forces in trusses into horizontal and vertical components, using trigonometric functions to calculate these components based on given angles.

What is the Pythagorean theorem used for in right triangles?

• Calculating the area of a triangle

• Finding the length of the hypotenuse

• Determining the perimeter of a triangle

• Calculating the volume of a triangle

Which trigonometric function is represented by the ratio of the opposite side to the hypotenuse?

• Cosine

• Sine

• Secant

• Tangent

In the example problem, which trigonometric function is used to find the hypotenuse when the opposite side and angle are known?

• Tangent

• Cotangent

• Sine

• Cosine

What is the value of the hypotenuse calculated in the example problem?

• 5.34 inches

• 3.6 inches

• 6.44 inches

• 4.3 inches

Which trigonometric function is used to find a missing angle when the opposite and adjacent sides are known?

• Cosecant

• Tangent

• Cosine

• Sine

What is the missing angle calculated in the example problem?

• 53.4 degrees

• 60 degrees

• 34 degrees

• 45 degrees

In resolving forces, what does the horizontal component of a force represent?

• The force at an angle

• The force in the horizontal direction

• The force in the vertical direction

• The total force

When resolving a force into components, which trigonometric function is used to find the vertical component if the angle is with respect to the horizontal?

• Cotangent

• Tangent

• Cosine

• Sine

If the angle is with respect to the vertical, which trigonometric function is used to find the horizontal component of the force?

• Secant

• Tangent

• Cosine

• Sine

What should you do if you are unsure about the orientation of the angle when resolving forces?

• Draw the triangle and identify the sides

• Guess the orientation

• Use the sine function for both components

• Use the cosine function for both components