Search our library of IB questions

Top answers

All subjects

A ball in a room is thrown with a speed v = 15 m/s at an angle 45 degrees above the horizontal. If the ceiling is 4 m high, will the ball hit the ceiling? If so, what is the minimum angle at which the ball will not hit the ceiling? Neglect air resistance.

Since we want to find the height reached by the ball, we only want to consider the vertical component of the ball's velocity. Using trigonometry, the y component will be:
v_y= 15 * sin (45)...

Answered by Hiro F. • Physics tutor

2102 Views

Describe the Process of DNA Replication

During DNA Replication, the existing molecule gets replicated, resulting in two semi-conservative DNA molecules. The enzyme helicase unwinds and unzips the double helix of the DNA, while ...

Answered by • Biology tutor

2939 Views

Write down the expansion of (cosx + isinx)^3. Hence, by using De Moivre's theorem, find cos3x in terms of powers of cosx.

First, we expand by using binomial expansion (it is always helpful to draw Pascal's triangle to find each term's coefficients): 1 1
1 2 1
1 3 3 1
Since the function is raised to the...

Answered by Hiro F. • Maths tutor

12675 Views

What is the limit for this function as x approaches 0? y(x)=(cos x)^(1/sin x)

When we try to simply compute y(0) we get 1 to infinity, which is indeterminate (we means we can either get 0, 1, infinity or God knows what else!). The way we want to approach these types of exercises is...

Answered by • Maths tutor

1652 Views

What conditions in pre-CCP China can help explain the rise of Mao?

This could be a very long answer, but can be briefly summarised into several factors. Firstly, political conditions in China were dire, due to over 50 years of political turmoil and the disintegration of...

Answered by • History tutor

1864 Views