Term
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Definition
| A quantity that has both magnitude and direction. |
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Term
| What is the product of a vector multiplied by a scalar? |
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Definition
V = vector
k = scalar
k*V is A vector with a direction parallel to the vector and a magnitude equal to k times the magnitude of the vector. |
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| How is a vector multiplied by a scalar algebraically? |
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Definition
| break up the vector into components, then multiply the components by the scalar. Example: nV = n (V (x-direction + V y-direction) |
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Term
| If two vectors, A and B, are added together, their resultant magnitude will be....." |
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Definition
| Break each vector into its components in the x and y direction. Then use the Pythagorean Theorem to determine the resultant vector's magnitude. |
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Term
| What is the resultant (magnitude and direction) of the vectors A = 5x and B = 8y |
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Definition
magnitude = 9.4
58 degrees
Make a triangle. Use the Pythagorean Theorem to get the magnitude. The angle is found using the tangent of the triangle. Angle = tan-1 (y/x) |
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Term
| Assume two forces are acting on an object. When will the magnitude of their resultant be the smallest? |
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Definition
| When the forces are acting in the same plane in opposite directions. The magnitude will be the difference between the two vectors. The angle between the two vectors will be 180 degrees. |
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Term
| To add two vectors graphically, which is used; the triangle method or the parallelogram method? |
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Definition
| Either one. Both are suitable for vector addition. |
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Term
| What is the resultant of the vectors A = 3x, B = -4y, and C = 2x + 7y |
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Definition
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Term
| How is a vector resolved in terms of its components? |
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Definition
| By expressing it as the sum of the products of each of the components multiplied by the corresponding unit vector along the x- and y-axis, i.e., F = iFx + jFy. The vectors i and j are special unit vectors that lie along the x- and y-axis, respectively. The vector k is also sometimes used, as a unit vector that lies along the z-axis. |
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Term
| For a freely falling object in projectile motion, what is the acceleration in the x-direction? |
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Definition
| Zero. Gravitational acceleration has only a downward, constant x-axis component with a magnitude of g. |
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Term
| What is the acceleration in the y-direction for a freely falling body in projectile motion? |
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Definition
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Term
| What is the magnitude of a unit vector? |
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Definition
| A unit vector has a magnitude of one. |
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Term
| If a system of forces comes into equilibrium, it is said to be balanced by a single force called a (n)__________________. |
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Definition
| equilibrant. An equilibrant is a single force needed to bring an unbalanced system into equilibrium such that the net force is zero. |
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Term
| If a 1 kg mass falls through the earth's atmosphere with a constant velocity, the retarding force of the atmosphere must be equal to _________. |
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Definition
| 9.8 N. Force acting on the mass is 9.8 N (W=mg; 1 kg x 9.8 m/x2); thus, if falling at constant velocity, the retarding force must be 9.8 N up. |
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Term
| What is meant by a rigid body being in static equilibrium? |
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Definition
| A rigid body is in static equilibrium when the sum of the forces and torques on it is zero. |
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Term
| What is the name of the quantity that has the units of kg m/s2? |
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Definition
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