# Tutor profile: Adriana D.

## Questions

### Subject: Trigonometry

What is the area of a right triangle whose hypotenuse is 5, and whose base is 3?

The area of a right triangle is always equal to 1/2 times its base times its height. Here, since you do not have its height, you must find that first. Using the Pythagorean Theorem we know that a^2 + b^2 = c^2 . c is always the hypotenuse and you can choose either a or b to be the base or height , respectively. Once you find the height, remember to multiply it times the base and then again by 1/2 to get the area. ( height = 4, area= (1/2)x3x4=6)

### Subject: Astronomy

Why do some stars explode?

The chemical reactions in the core of a star release a lot of energy and pressure that push outward. Meanwhile, gravity is pulling inward and the balance of the two keeps it all together. In the core, heavier and heavier elements are being forged until they reach a limit that can't be sustained. If the star is massive enough, gravity takes over big time until it all comes crashing down on the core. The explosion is a sort of bouncy-ball effect where all the outer layers are ejected into a brilliant nova or supernova

### Subject: Physics

What is the difference between speed, velocity and acceleration?

Speed is simply how fast you are moving ( i.e. I drive 70mph). Velocity is how fast with a direction (i.e. I drive 70mph NORTH). Acceleration is the change in velocity over time. It exists whenever you adjust your speed, turn away from a straight path, or both.

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