science
Grade-11
Easy
Question
If a boat moves on the river with the speed of 50 km/h and also moves in other directions relatively with a speed of 30 km/h. What is the speed of the boat?
- 20
- 15
- 30
- 40
Hint:
40 m/s
The correct answer is: 40
Given:
The relative velocity of the boat as it travels downstream V1 = 50kmh-1
The relative velocity of the boat as it travels upstream V2 = 30kmh-1
To find:
The actual speed of the boat =?
Solution:
Case 1: when a boat flows downstream
V1 = Vboat + Vriver
50 = Vboat + Vriver -1
Case 2: when a boat flows upstream
V2 = Vboat - Vriver
30 = Vboat - Vriver -2
From equation 1 and 2
2Vboat = 80 ms-1
Vboat = 40ms-1
Answer:
The actual velocity of the boat is 40ms-1
Related Questions to study
science
Relative motion can be used to evaluate ________.
Relative motion can be used to evaluate ________.
scienceGrade-11
science
Newton’s laws are not applicable in ___________.
Newton’s laws are not applicable in ___________.
scienceGrade-11
science
If a man jumps out of running train, then ____________.
If a man jumps out of running train, then ____________.
scienceGrade-11
science
Drawing a diagram and explaining the motion is called as ________
Drawing a diagram and explaining the motion is called as ________
scienceGrade-11
science
On Earth, if a body is in the car and the car is moving with the uniform velocity, then the body in the vehicle is ___
On Earth, if a body is in the car and the car is moving with the uniform velocity, then the body in the vehicle is ___
scienceGrade-11
science
Concerning the motion, there are ______ Newton’s laws.
Concerning the motion, there are ______ Newton’s laws.
scienceGrade-11
science
If a body is in motion, it is changing _____ with respect to the time.
If a body is in motion, it is changing _____ with respect to the time.
scienceGrade-11
science
A student is sitting on a chair. One force that is acting on the student is the pull of gravity. According to Newton’s third law, there must be another force acting, which is
A student is sitting on a chair. One force that is acting on the student is the pull of gravity. According to Newton’s third law, there must be another force acting, which is
scienceGrade-11
science
The horse pulling the wagon is able to move forward because of
The horse pulling the wagon is able to move forward because of
scienceGrade-11
science
The mass of an object is 50kg, calculate its weight?
The mass of an object is 50kg, calculate its weight?
scienceGrade-11
science
Name the force through which the Earth and the comet interact
Name the force through which the Earth and the comet interact
scienceGrade-11
