A pulley system lifts a 500-lb. block 2.0 feet with an effort of only 50 lb. If the 50 lb. moves 30 feet, calculate the efficiency of the pulley system.

A sample of the mineral calcite has a volume of 15 cm³ and a mass of 40.5 g. What is the density of the calcite? A. 0.37 g/cm³B. 2.7 g/cm³C. 55.5 g/cm³D. 607.5 g/cm³

Which of these has the most inertia? A. a parked bus B. a 10-kilogram mass C. a 16-pound bowling ball D. a wheelbarrow full of bricks

A space vehicle is traveling at 4150 km/h relative to the Earth when the exhausted rocket motor (mass 4m) is disengaged and sent backward with a speed of 79 km/h relative to the command module (mass m).

Why are summers oftenmuch warmer than winters

A physicist makes a cup of instant coffee and notices that, as the coffee cools, its level drops 3.00 mm in the glass cup.

Which vector should be negative? any vector whose magnitude is less than 1 a displacement in the direction North any vector whose magnitude is greater than 1 the velocity of a falling object

Acceleration is a scalar quantity true or false

Find a numerical value for rhoearth, the average density of the earth in kilograms per cubic meter. Use 6378km for the radius of the earth, G=6.67*10-11m3 / (kg⋅s2), and a value of g at the surface of 9.80m/s2.

The driver of a car traveling at 32 m/s applies the brakes and undergoes a constant deceleration of 2.25 m/s^2.

The ability of an object to vibrate by absorbing energy at its natural frequency is called?