Physical Science Exam #1 Study Guide

A 2-kg book is held 1 m above the floor for 50 s. The work done is -0 J -10.2 J -100 J -980 J

0 J

A crane exerts an upward force of 200 N on a 20-kg crate. The crate's upward acceleration is -0 -0.2 m/s^2 -10 m/s^2 -98 m/s^2

0.2 m/s^2

A force that gives a 2-kg object an acceleration of 1.6 m/s^2 would give an 8-kg object an acceleration of -0.2 m/s^2 -0.4 m/s^2 -1.6 m/s^2 -6.4 m/s^2

0.4 m/s^2

The time needed for a car whose speed is 60 km/h to travel 800 m is -0.48 min -0.8 min -4.5 min -13 min

0.8 min

The stars in a constellation -are about the same age -are about the same distance from the earth -form a pattern in the sky as seen from the earth -are members of the solar system

form a pattern in the sky as seen from the earth

The weight of an object is -the same everywhere on the earth's surface -greater at the poles than at the equator -less at the poles than at the equator -any of these choices, depending on the phase of the moon

greater at the poles than at the equator

A stone is thrown upward from a roof at the same time as another identical stone is dropped from there. The two stones -reach the ground at the same time -have the same speed when they reach the ground have the same acceleration when they reach the ground -none of the choices are correct

have the same speed when they reach the ground have the same acceleration when they reach the ground

When first proposed, a scientific idea is usually called a -hypothesis -law -theory -model

hypothesis

What distinguishes the scientific method from other ways of looking at the natural world is -the eternal truth of its laws and theories -its replacement of existing laws and theories at regular intervals -its reliance on the opinions of expert scientists to decide which laws and theories to believe -its reliance on experiment and observation

its reliance on experiment and observation

An object that has linear momentum also has -acceleration -angular momentum -kinetic energy -potential energy

kinetic energy

On a molecular level heat is -kinetic energy -potential energy -mass energy -momentum

kinetic energy

If a spaceship 100 m long when at rest on the earth were to travel at nine-tenths the speed of light, its length as measured by an observer on the earth would be -0 -less than 100 m -100 m -more than 100 m

less than 100 m

In the formula Eo = mc^2, the symbol c represents the speed of -an object of mass m -the observer -sound -light

light

The length of the year is -less than 365 days -exactly 365 days -more than 365 days -any of the above choices, depending on the year

more than 365 days

Scientific theories -must be constantly reviewed to see whether they are in accord with new experimental observations -represent guesses that have not yet been compared with observational data -are summaries of particular experiments -are laws of nature not subject to revision

must be constantly reviewed to see whether they are in accord with new experimental observations

The watt is a unit of -energy -work -momentum -power

power

A rocket is fired in space. As it moves, the total momentum of the rocket and its exhaust gases -decreases -remains the same -increases -any of the choices could be correct, depending on the nature of the rocket

remains the same

A gold ball and a ping-pong ball are dropped in a vacuum chamber. When they have fallen halfway down, they have the same -speed -potential energy -kinetic energy -rest energy

speed

A day is the time needed for -the sun to drift completely around the sky -the moon to drift completely around the sky -the earth to completely on its axis -none of the choices are correct

the earth to completely on its axis

Which of the following quantities is always the same to all observers? -time intervals -the speed of an object -the speed of sound -the speed of light

the speed of light

A year is the time needed for -the sun to drift completely around the sky -the moon to drift completely around the sky -the earth to completely on its axis -none of the choices are correct

the sun to drift completely around the sky

An object moving in a circle at constant speed is accelerated -in the direction of its motion -toward the center of the circle -away from the center of the circle -any of these choices, depending on the circumstances

toward the center of the circle

A car starts from rest and reaches a speed of 15 m/s in 10s. Its acceleration is -0.67 m/s^2 -1.5 m/s^2 -6.7 m/s^2 -15 m/s^2

1.5 m/s^2

A weightlifter raises a 200-kg barbell through a height of 2 m in 2.2 s. The average power he develops during the lift is -0.18 kW -0.89 kW -1.78 kW -8.62 kW

1.78 kW

A total of 4900 J is expended in lifting a 50-kg mass. The mass is raised to a height of -10 m -98 m -960 m -245,000 m

10 m

In 6 min a person running at 10 km/h covers a distance of -167 m -600 m -1000 m -1667 m

1000 m

The KE of a 900-kg whose speed is 60 km/h is (hint: convert speed from km/h to m/s) -12.8 kJ -125 kJ -1.23 MJ -1.62 MJ

125 kJ

A snail travels 45 cm in 20 min. Its average speed is -2.25 cm/h -15 cm/h -90 cm/h -135 cm/h

135 cm/h

A person is 5 ft 8.0 in. tall. This is equivalent to -173 cm -177 cm -207 cm -223 cm

173 cm

A net force of 10 N gives an object an acceleration of 5 m/s^2. What net force would give the same object an acceleration of 1 m/s^2? (hint: Use force equation to first find the mass of object) -1 N -2 N -5 N -50 N

2 N

The linear momentum of a 400-kg giraffe galloping at 5 m/s is -80 kgm/s -2,000 kgm/s -5,000 kgm/s -19,600 kgm/s

2,000 kgm/s

The size of a picture is given as 84 cm by 255 cm. Since (0.84m)x(2.55m) = 2.142 m^2 exactly, the area of the picture is correctly expressed as -2.142 m^2 -2.14 m^2 -2.1 m^2 -2 m^2

2.1 m^2

The number of cubic centimeters in a cubic foot is about -1.7 x 10^3 -1.7 x 10^4 -2.8 x 10^4 -1.7 x 10^5

2.8 x 10^4

The mass of a sack of potatoes whose weight is 200 N is -20.4 kg -91 kg -210 kg -440 kg

20.4 kg

A stone dropped from a cliff reaches the ground in 4s. The stone's speed is then approximately -10 m/s -40 m/s -196 m/s -392 m/s

40 m/s

A 50-kg person weighs -5.1 N -23 N -110 N -490 N

490 N

The discovery that the planetary orbits are ellipses rather than circles was made by -Ptolemy -Copernicus -Kepler -Newton

Kepler

The scientist who showed that gravity accounts for Kepler's laws of planetary motion was -Newton -Brahe -Einstein -Galileo

Newton

In which one or more of the following is the earth assumed to be the center of the universe? -The Ptolemaic system -The Copernican system -Kepler's laws of planetary motion -Newton's law of gravity

The Ptolemaic system