Why can friction make observing Newton's first law of motion difficult?

Polychlorinated biphenyls (PCBs) have been banned because they are an environmental hazard. Which of the following was NOT a reason for banning them?

What will a spring scale read for the weight of a 57.0-kg woman in an elevator that moves upward with constant speed of 5.0 m/s?

17. If you looked at a light through the lenses from two polarizing sunglasses that were overlapped at right angles to each other, all of the light would pass through. most of the light would pass through. little of the light would pass through.

In the Earth's mantle, heat is transferred in large convection currents. Within these currents, A. cooler rock rises and hotter rock sinks. B. hotter rock rises and cooler rock sinks. C. hotter and cooler rock sink but do not rise.

A 1200 kg car traveling north at 14 m/s is rear-ended by a 2000 kg truck traveling at 30 m/s. What is the total momentum before and after the collision?

Light from the sun travels through space to Earth's atmosphere. Which will light waves do when they move from empty space into matter made up of different gases? A. move at the same speed B. move faster as they transmit C. slow down and refract D.

A 12.5 kg box sliding on a frictionless flat surface tuns into a fixed spring which compresses at a distance x = 14.1 cm. the spring constant is 94.5 kN/m Find the initial speed of the box

An earth scientist who studies hydrosphere

In 1991 four English teenagers built an eletric car that could attain a speed of 30.0m/s. Suppose it takes 8.0s for this car to accelerate from 18.0m/s to 30.0m/s. What is the magnitude of the car's acceleration?

A capacitor with a capacitance of 490 μf is charged to a voltage of 260 v. then a wire is connected between the plates. how many joules of thermal energy are produced as the capacitor