NCERT Solutions
Board Paper Solutions
Ask & Answer
School Talk
Login
GET APP
Login
Create Account
Popular
Latest
Expert Answers
ALL
R. Lasyapriya
Subject: Science
, asked on 5/3/18
13 question
Define Power Two girls A and B each of weight 50Kg climb up a rope through a height of 10 m . Girl A takes 20s whereas B takes 50 s to accomplish. This task calculate the power expended by each girl.
Answer
1
Prithika
Subject: Science
, asked on 3/3/18
why we take the potential energy of a pendulum zero at is mean position?
Answer
1
Idris Padiwala
Subject: Science
, asked on 25/2/18
A car moving on a plane surface applies breaks to reduce it's speed from 10m/s to 5m/s. The mass of the vehicle is 150g. Find the work done by brakes
Answer
1
Noufiya
Subject: Science
, asked on 24/2/18
Plz solve this one also
Q.(a) Define the work done by a constant force. Write its SI unit and define this unit.
(b) A 3000 kg truck moving at a speed of 72 km/h stops after covering some distance. The force applied by brakes is 24000 N. Compute the distance covered and work done by this force.
Answer
1
Noufiya
Subject: Science
, asked on 24/2/18
....???
Q. Calculate the electricity bill amount for a month of 31 days, if the following devices are used as specified :
(a) 3 bulbs of 40 W for 6 hours.
(b) 4 tubelights of 50 W for 8 hours.
(c) A TV of 120 W for 6 hours.
Given the rate of electricity is Rs. 2.50 per unit.
Answer
1
Noufiya
Subject: Science
, asked on 23/2/18
Solve:
9. One day Disha who is studying in class IX went to mother diary's vegetable shop where she found some umbrella like structures being sold. She could immediately identify them.
(a) What is that structure?
(b) To which kingdom does that belong ?
(c) Write two characteristic features of organisms belonging to this kingdom.
10. Differentiate between communicable and non-communicable diseases in two points. Give one example of each.
11. " In an organism, different organs of different systems show interaction and interdependence." Justify this statement given an example.
Answer
1
Sahil.....
Subject: Science
, asked on 20/2/18
What is work energy theorem please answer guys .Not there in ncert
Answer
1
Ansh Rohatgi
Subject: Science
, asked on 19/2/18
Q 21 part b
b) A student lifts an object in the upward direction. In doing so he applies force on the object in the upward direction, displacing the object upwards. However, the force of gravity is also acting on the object.
i) State the direction in which the force of gravity is acting on it.
ii) Which of these forces is doing positive work?
iii) Which of these forces is doing negative work?
Justify your answer.
Answer
4
Sambartak Ghosh
Subject: Science
, asked on 17/2/18
Science questions basically from different chapters
Answer
1
Aviral Pandey
Subject: Science
, asked on 17/2/18
4 m
^{3}
of water is to be pumped to a height of 20m and forced into a reservoir at a pressure of 2 * 10
^{5}
N/m
^{2}
. Find the work done by the motor. (External pressure = 10
^{5}
N/m
^{2}
)
Answer
3
Fatima Nadeem
Subject: Science
, asked on 15/2/18
Solve this :
88. If K.E. of a bod increases by 0.1%, the percent increase in its momentum would be :
(1) 10% (2) 1%
(3) 0.1% (4) 0.05%
Answer
2
Rishika
Subject: Science
, asked on 14/2/18
prove law of conservation of energy
Answer
1
Aryaman Kumar
Subject: Science
, asked on 11/2/18
Question no. 16 part 2 and 3
16.
Figure shows a simple predulum consisting a bob of mass 100 gm.
Initially the bob of pendulum is at rest at 0. It is displaced to one side at A. The height of A above O is 7 cm.
(ii) What is the value of kinetic energy of bob at mean position O ?
(iii) What is the value of kinetic and potential energy of bob at position P.
Answer
1
Sameer
Subject: Science
, asked on 11/2/18
What is the work to be done to increase the velocity of a car from 18 km/hr to 72 km/hr if the mass of the car is 1500 kg ? pls. pls. pls. answer the question ! i need this urgently .
Answer
2
Vaibhav Kumar
Subject: Science
, asked on 8/2/18
What is the work to be done to increase the velocity of a car from 35 km/hr to 65 km/hr.If the mass of the car is 2000 kg
Answer
3
Prev
1
2
3
4
5
Next
What are you looking for?

Define Power Two girls A and B each of weight 50Kg climb up a rope through a height of 10 m . Girl A takes 20s whereas B takes 50 s to accomplish. This task calculate the power expended by each girl.

Q.(a) Define the work done by a constant force. Write its SI unit and define this unit.

(b) A 3000 kg truck moving at a speed of 72 km/h stops after covering some distance. The force applied by brakes is 24000 N. Compute the distance covered and work done by this force.

Q. Calculate the electricity bill amount for a month of 31 days, if the following devices are used as specified :

(a) 3 bulbs of 40 W for 6 hours.

(b) 4 tubelights of 50 W for 8 hours.

(c) A TV of 120 W for 6 hours.

Given the rate of electricity is Rs. 2.50 per unit.

9. One day Disha who is studying in class IX went to mother diary's vegetable shop where she found some umbrella like structures being sold. She could immediately identify them.

(a) What is that structure?

(b) To which kingdom does that belong ?

(c) Write two characteristic features of organisms belonging to this kingdom.

10. Differentiate between communicable and non-communicable diseases in two points. Give one example of each.

11. " In an organism, different organs of different systems show interaction and interdependence." Justify this statement given an example.

b) A student lifts an object in the upward direction. In doing so he applies force on the object in the upward direction, displacing the object upwards. However, the force of gravity is also acting on the object.

i) State the direction in which the force of gravity is acting on it.

ii) Which of these forces is doing positive work?

iii) Which of these forces is doing negative work?

Justify your answer.

^{3}of water is to be pumped to a height of 20m and forced into a reservoir at a pressure of 2 * 10^{5}N/m^{2}. Find the work done by the motor. (External pressure = 10^{5}N/m^{2})Solve this :88. If K.E. of a bod increases by 0.1%, the percent increase in its momentum would be :

(1) 10% (2) 1%

(3) 0.1% (4) 0.05%

16. Figure shows a simple predulum consisting a bob of mass 100 gm.

(ii) What is the value of kinetic energy of bob at mean position O ?

(iii) What is the value of kinetic and potential energy of bob at position P.