Complete each nuclear fission reaction.

235

92

U +

1

0

n →

90

36

Kr +

A

56

Ba + 3

1

0

n

what is A?

The Curies took pure uranium and a uranium-containing substance. When they measured the amount of radioactivity, there was more in the uranium-containing substance than the pure uranium. Which idea did the Curies most likely develop?

The softest and hardest minerals are: softest hardest

8. The coils of a solenoid are stretched so that the length of the solenoid is twice its original length.

If the torque on an object adds up to zero the forces on it also add up to zero. the object could be accelerating linearly but it could not be turning. the object cannot be turning. the object is at rest.

Which of the following combinations of elements is most likely to produce covalent bonds? a. hydrogen & helium b. sodium & magnesium c. fluorine & bromine d. aluminum & bromine

A tree is standing in the middle of a meadow. As you watch, the wind begins to blow and the tree bends. Which statement best explains how you could tell that a net force was acting on the tree? OA) The tree had momentum.

Consider two cars, a 700kg Porsche and a 600kg Honda Civic. The Porsche is speeding along at 40 m/s (mph) and the Civic is going half the speed at 20 m/s.

Which statement about an electron in the 4d state is correct? A. The magnitude of its orbital angular momentum is 6√ℏ. B. The largest orbital angular momentum it could have in any given direction is 4ℏ. C.

A D note has a frequency of 587.33 Hz. Calculate its wavelength in meters. The speed of sound is 343 m/s

A cyclist allows his bike to roll down a hill without pedaling. Towards the bottom of the hill he applies his brakes. The bike comes to a stop. Applying the brakes causes the brakes to warm up. Describe the energy transfers that have occurred.