Mutiple choice:
A car travelling at 10 m/s accelerates at 3 m/s^2. Its new velocity is
A.) 12 m/s B.) 22m/s C.) 17 m/s D.) Can not be determined.
Which of the following is not acceleration?
A.) rate of change of speed in a particular direction B.) rate of change of motion in a particular direction. C.) rate of change of velocity D.) rate of change of displacement
An object will weigh least on
A.) Jupiter B.) Pluto C.) Earth D.) Saturn
On a graph of distance verse elasped time, the slope of the tangent to the curve at any single point is
A.) average speed B.) constant speed C.) variable speed D.) instantenous speed
An object is accelerated from the rest of a rate at 2 m/s^2. At the end of 8 seconds, the magnitude of the velocity is
A.) 2.0 m/s B) 6.0 m/s C.) 8.0 m/s D.) 16 m/s
After a body has fallen freely from rest to 4.0 seconds, its velocity is apporoximentaly
A) 20 m/s B) 40 m/s C.) 60 m/s D.)80 m/s
A force with a magnitude of 100 newtons acts at a 30 degree angle from the horizon. The "X" component of this force is
a) 87 newtons B) 50 newtons C) it is at rest D) its motion is changed
An object is not considered to be in a state if equilibrium if
A) it is not moving at constant speed in a straight line B) there is an unbalanced force acting on the body
C) It is at rest D) its motion is unchanged
1D. Cannot be determined, because we don't know the time.
2D.
5D.V = a*t = 2m/s^2 * 8s. = 16 m/s.
6B. V = Vo + g*t = 0 + 10*4 = 40 m/s.
7A. X = 100*cos 30 = 87 N.
8B.
To solve these multiple-choice questions, we will go through each option and determine the correct answer.
1. A car traveling at 10 m/s accelerates at 3 m/s^2. Its new velocity is:
To find the new velocity, we can use the formula: final velocity = initial velocity + (acceleration * time). Plugging in the values, we get:
Final velocity = 10 m/s + (3 m/s^2 * 1 s) = 13 m/s
Since none of the given options match 13 m/s, we can conclude that the answer is D.) Can not be determined.
2. Which of the following is not acceleration?
Acceleration is the rate of change of velocity. Therefore, option D.) rate of change of displacement is not considered acceleration. Displacement refers to the change in position, while acceleration deals with changes in velocity or speed.
3. An object will weigh least on:
Weight is influenced by the gravitational force acting on an object, which depends on the mass of the object and the gravitational field strength. The gravitational field strength varies on different celestial bodies. Therefore, the object will weigh the least on B.) Pluto, as it has the lowest gravitational field strength among the given options.
4. On a graph of distance versus elapsed time, the slope of the tangent to the curve at any single point is:
The slope of the tangent to the curve on a distance-time graph represents the rate of change of distance with respect to time at that specific point. This corresponds to the object's instantaneous speed or velocity at that time. Therefore, the answer is D.) instantaneous speed.
5. An object is accelerated from rest at a rate of 2 m/s^2. At the end of 8 seconds, the magnitude of the velocity is:
To find the magnitude of the velocity after 8 seconds, we can again use the formula: final velocity = initial velocity + (acceleration * time). Given that the initial velocity is 0 m/s, we have:
Final velocity = 0 m/s + (2 m/s^2 * 8 s) = 16 m/s. Thus, the answer is D.) 16 m/s.
6. After a body has fallen freely from rest for 4.0 seconds, its velocity is approximately:
When an object falls freely due to gravity, its velocity increases at a constant rate. The acceleration due to gravity on Earth is approximately 9.8 m/s^2. After 4 seconds of free fall, the velocity can be calculated using the formula: final velocity = initial velocity + (acceleration * time). Given that the initial velocity is 0 m/s, we have:
Final velocity = 0 m/s + (9.8 m/s^2 * 4 s) = 39.2 m/s ≈ 40 m/s. Therefore, the answer is B.) 40 m/s.
7. A force with a magnitude of 100 newtons acts at a 30-degree angle from the horizontal. The "X" component of this force is:
To find the "X" component of the force, we can use the formula: horizontal component = force * cos(angle). Plugging in the values, we get:
Horizontal component = 100 N * cos(30°) ≈ 100 N * 0.866 ≈ 86.6 N ≈ 87 N. Thus, the answer is A.) 87 newtons.
8. An object is not considered to be in a state of equilibrium if:
Equilibrium refers to a state in which the net force acting on an object is zero, meaning there is no unbalanced force. Therefore, the answer is B.) there is an unbalanced force acting on the body.