science
Grade-9
Easy
Question
A ball is dropped from the top of a building. If the reference direction is taken to be downwards, the acceleration of the ball is ___ m/s2.
- 10
- 9.8
- 0
- -9.8
Hint:
under free fall, an object experience acceleration due to gravity.
The correct answer is: 9.8
A ball is dropped from the top of a building. If the reference direction is taken to be downwards, the acceleration of the ball is 9.8 m/s2.
The direction of acceleration is in the same direction of motion. hence the acceleration will be positive.
Related Questions to study
science
Which of the following quantities cannot be calculated by directly using the first equation of motion?
Which of the following quantities cannot be calculated by directly using the first equation of motion?
scienceGrade-9
science
1 minute = ____ seconds.
1 minute = ____ seconds.
scienceGrade-9
science
1 km = ___m.
1 km = ___m.
scienceGrade-9
science
Which of the following is called the position-velocity relation?
Which of the following is called the position-velocity relation?
scienceGrade-9
science
1 km/h = ___ m/s.
1 km/h = ___ m/s.
scienceGrade-9
science
Which of the following quantities does the second equation of motion not have?
Which of the following quantities does the second equation of motion not have?
scienceGrade-9
science
A ball is thrown upwards. Which of the following is false about its motion?
A ball is thrown upwards. Which of the following is false about its motion?
scienceGrade-9
science
A racing car started from rest and increased its speed to 120 m/s in a minute. The acceleration of the car is ___ m/s2.
A racing car started from rest and increased its speed to 120 m/s in a minute. The acceleration of the car is ___ m/s2.
scienceGrade-9
science
A car covers equal distances at equal intervals of time. Which of the following is false about the motion of the car?
A car covers equal distances at equal intervals of time. Which of the following is false about the motion of the car?
scienceGrade-9
science
In which of the following cases are the equations of motion not valid?
In which of the following cases are the equations of motion not valid?
scienceGrade-9
science
The driver of a car moving at a speed of 20 m/s applies the brakes on seeing a rock at some distance. The car stops after 12 s. The acceleration of the car is -___m/s2.
The driver of a car moving at a speed of 20 m/s applies the brakes on seeing a rock at some distance. The car stops after 12 s. The acceleration of the car is -___m/s2.
scienceGrade-9
science
A car starts from rest and keeps increasing its speed by 3 m/s every second. The final speed that it reaches after 20 seconds is _____.
A car starts from rest and keeps increasing its speed by 3 m/s every second. The final speed that it reaches after 20 seconds is _____.
scienceGrade-9
science
A vehicle moving at a speed of 12 m/s accelerates at a rate of 6 m/s2 for 7 seconds. The final velocity of the vehicle is _____.
A vehicle moving at a speed of 12 m/s accelerates at a rate of 6 m/s2 for 7 seconds. The final velocity of the vehicle is _____.
scienceGrade-9
science
A bus starts from rest and attains a velocity of 30 m/s in 5 s. Its acceleration is ____ m/s2.
A bus starts from rest and attains a velocity of 30 m/s in 5 s. Its acceleration is ____ m/s2.
scienceGrade-9
science
The area under a v-t graph gives the _____ of the body.
The area under a v-t graph gives the _____ of the body.
scienceGrade-9
