Angle of Elevation and Depression

Q.

The angle formed by the line of sight with the horizontal, when the point being viewed is above the horizontal level is called:

1. Angle of elevation

2. Angle of depression

3. Obtuse angle

4. Vertical angle

Q. If the length of the shadow of a tower increases, then the angle of elevation of the sun will

1. increase
2. decrease
3. remains same
4. None

Q.

The angle of elevation is the angle between the line of sight of an observer below his horizontal line of sight.

1. False

2. True

Q.

A car with vertical windshield moves in a rainstorm at a speed of $40km/hr$. The rain drops fall vertically with a constant speed of $20m/s$. The angle at which raindrops strike the windshield is:

Q. 42. As observed from the top of the light house of height h m the angles of depression of two ships approaching it are α and β If one ship is coming from west and the other is coming from south. fnd the dstance the ships

Q.

A tower is $100\sqrt{3}$ m high. Find the angle of elevation of its top from a point 100 m away from its foot.

1. ${15}^{\circ }$

2. ${45}^{\circ }$

3. ${30}^{\circ }$

4. ${60}^{\circ }$

Q. If a man is looking up at the tip of an electric pole, then the angle between the line joining the man's eye and the tip of the electric pole is called as the angle of elevation.

1. True
2. False

Q. A ladder on the platform of a fire brigade van can be elevated at an angle of ${70}^{\circ }$to the maximum. The length of the ladder can be extended upto $20m$. If the platform is 2m above the ground, find the maximum height from the ground upto which the ladder can reach.$(\sin {70}^{\circ }=0.94)$

1. $20.2m$
2. $18.2m$
3. $20.8m$
4. $18.8m$

Q.

An observer 2.25 m tall is 42.75 m away from a chimney. The angle of elevation of the top of the chimney from her eyes is ${45}^{\circ }$. What is the height of the chimney?

1. 35 m

2. 40 m

3. 45 m

4. 50 m

Q. From the foot and the top of a building of height $230m$, a person observes the top of a tower with angles of elevation of $\beta$ and $\alpha$ respectively. What is the distance between the top of the building and the top of the tower if $\tan \alpha =\frac{5}{12}$ and $\tan \beta =\frac{4}{5}$.

1. $400m$
2. $250m$
3. $600m$
4. $650m$

Q.

An observer 2.25 m tall is 42.75 m away from a chimney. The angle of elevation of the top of the chimney from her eyes is ${45}^{\circ }$. What is the height of the chimney?

1. 40 m

2. 35 m

3. 50 m

4. 45 m

Q.

If a man is looking up at the top of an electric pole, then the line joining the man's eye and the tip of the electric pole is called as the line of elevation.

1. True

2. False

Q.

State whether the given statement is true or false:

The angle of elevation is the angle between the line of sight of an observer from above and the object below his horizontal line of sight.

1. True

2. False

Q.

An observer 2.25 m tall is 42.75 m away from a chimney. The angle of elevation of the top of the chimney from her eyes is ${45}^{\circ }$. What is the height of the chimney?

1. 40 m

2. 35 m

3. 45 m

4. 50 m

Q.

The angle of elevation of the top of a tower from the top and foot of 100m building are ${30}^{\circ }and{45}^{\circ }$ respectively. The height of the tower is

1. $50(3-\sqrt{3})m$

2. $50(3+\sqrt{3})m$

3. $50\sqrt{3}m$

4. 150 m

Q. ___ is defined as the line drawn from the eye of the observer to the the object viewed by the observer.

1. Line of sight
2. Vertical line
3. Transversal line
4. Horizontal line

Q. If the angle of depression from a lighthouse of two ships situated in the same line with the lighthouse are ${60}^{\circ }\text{and}{30}^{\circ }$ and if the nearer ship is $150m$ away from the lighthouse, then find the distance of the other ship from the lighthouse. $\left[4\text{Marks}\right]$

Q.

State whether the given statement is true or false:

The angle of elevation is the angle between the line of sight of an observer from above and the object below his horizontal line of sight.

1. True

2. False

Q.

State whether the given statement is true or false:

The angle of depression is the angle between the line of sight of an observer below his horizontal line of sight.

1. True

2. False

Q. The angle formed by line of sight with the horizontal, when we lower our head to look at an object is called ____.

1. angle of depression
2. acute angle
3. obtuse angle
4. angle of elevation

Q.

The angle of elevation of an aeroplane from a point on the ground is ${45}^{\circ }$. After a flight of 15 seconds, the angle of elevation changes to ${30}^{\circ }$. If the aeroplane is flying at a height of 3000 m, then find the speed of the plane.

$(\text{Take}\sqrt{3}=1.732)$

1. 146.4 m/s

2. 150 m/s

3. 150 km/h

4. 146.4 km/h

Q. __ is the angle formed by the line of sight with the horizontal when we raise our head to look at an object.

1. Angle of elevation
2. Obtuse angle
3. Angle of depression
4. Right angle