Physics - Semester 2, Test 1 Review

A person conducts a video analysis experiment to determine the acceleration due to gravity near the earth's surface. Her velocity-time graph yields the equation v = -(978cm/s^2)t + 332cm/s. The accepted value for the acceleration due to gravity is 9.81m/s^2. The percent error of her measured value compared to the accepted value is... - 4% - 98% - 0.4% - 199%

0.4%

Ten seconds after starting from rest, a freely falling object on earth will have a speed of about... - 500m/s - 50m/s - 10m/s - 100m/s

50m/s

One half second after starting from rest, a freely falling object on earth will have a speed of about... - 10m/s - 2.5m/s - 5m/s - 20m/s

5m/s

A person conducts a video analysis experiment to determine the acceleration due to gravity near the earth's surface. Her velocity-time graph yields the equation v = -(978cm/s^2)t + 332cm/s. Her position data yields the curve fit with an equation of x = -(482cm/s^2)t^2 + (381cm/s)t + 57.5cm. The shape of this graph is a... - concave up parabola - steepening curve - concave down parabola - flattening curve

Concave down parabola

If a projectile (free falling object) is fired straight up at a speed of 10m/s, the total time to return to its starting point is about... - 1 second - 2 seconds - 10 seconds - 20 seconds

2 seconds

If an object were equipped with a speedometer and allowed to fall freely on a planet where the acceleration due to gravity is 20m/s^2, the reading on the speedometer would increase each second by... - 20m/s - 10m/s - 30m/s - 40m/s

20m/s

In the absence of air resistance, objects fall at constant...

Acceleration

A person conducts a video analysis experiment to determine the acceleration due to gravity near the earth's surface. Her velocity-time graph yields the equation v = -(978cm/s^2)t + 332cm/s. The value for the acceleration due to gravity she found was... - -9.8m/s^2 - -1956cm/s^2 - -459cm/s^2 - -978cm/s^2

-978cm/s^2

The vertical height attainted by a basketball player who achieves a hang time of a full 1 second is about... - 2.5m - 0.8m - 1.0m - 1.2m

1.2m d = di + vi(t) + 1/2at^2 0 = di + 0(0.5s) + 1/2(-9.8)(0.5)^2 0 = di + 0 + 1/2(-4.9)(0.25) 0 = di + (-1.225) di = 1.225 --> 1.2m

Suppose a jumper claims a hang time of 2 seconds. Then that jumper must be able to jump a vertical distance of... - 1m - 3m - 5m - 2m

5m d = di + vi(t) + 1/2at^2 0 = di + 0(1) + 1/2(-9.8)(1)^2 0 = di + 0 + (-4.9)(1) 0 = di + (-4.9) di = 4.9 --> 5m

A person conducts a video analysis experiment to determine the acceleration due to gravity near the earth's surface. Her velocity-time graph yields the equation v = -(978cm/s^2)t + 332cm/s. The average acceleration due to gravity for her experiment is... - 964cm/s^2 - 971cm/s^2 - 978cm/s^2 - 981cm/s^2

971cm/s^2

Suppose an object is in free fall. Each second the object falls... - with the same average speed - a larger or smaller distance than the second before - a larger distance than in the second before - the same distance as in the second before

A larger distance than in the second before

Of a freely falling object were somehow equipped with a speedometer, its speed reading would increase each second by... - about 10m/s - about 15m/s - about 5m/s - a variable amount

About 10m/s

A ball tossed vertically upward rises, reached its highest point, and then falls back to its starting point. During this time, the acceleration of the ball is always... - directed upward - in the direction of motion - opposite its velocity - directed downward

Directed downward

A ball is thrown upwards and caught when it comes back down. In the absence of air resistance, the speed of the ball when caught would be... - less than the speed it had when thrown upwards - the same as the speed it had when thrown upwards - more than the speed it had when thrown upwards

The same as the speed it had when thrown upwards

A person conducts a video analysis experiment to determine the acceleration due to gravity near the earth's surface. Her velocity-time graph yields the equation v = -(978cm/s^2)t + 332cm/s. If she used a coordinate system in which the up direction is (+), you can conclude that the ball was initially... - thrown upward - thrown downward - released from rest - moving at a constant speed

Thrown upward

As an object falls freely in a vacuum, its... - velocity increases - acceleration increases - both velocity and acceleration increase - neither velocity nor acceleration increase

Velocity increases

A person conducts a video analysis experiment to determine the acceleration due to gravity near the earth's surface. Her velocity-time graph yields the equation v = -(978cm/s^2)t + 332cm/s. What would be the velocity equation for this object if the experiment were repeated on the moon (assume the same xi and vi), where g = 1.67m/s^2? - v = -(981cm/s^2)t + 332cm/s - v = -(167cm/s^2)t + 332cm/s - v = -(83.5cm/s^2)t + 332cm/s - v = -(167cm/s^2)t + 57.5cm/s

v = -(167cm/s^2)t + 332cm/s