A massless string connects two pulley of masses ' ' and '' respectively as shown in the figure.
The heavier pulley is fixed and free to rotate about its central axis while the other is free to rotate as well as translate. Find the acceleration of the lower pulley if the system was released from the rest. [Given, ]
Not understanding sir
View Full Answer(2)Two particles of mass 5kg and 10kg respectively are attached to the two ends of a rigid rod of length 1m with negligible mass. The centre of mass of the system from the 5kg particle is nearly at a distance of:
Option: 1 33 cm
Option: 2 50 cm
Option: 3 67 cm
Option: 4 80 cm
Here, m1 = 5 kg
r = 1 m
m2 = 10 kg
By putting this value we will get 0.666667 meter
or we can write = 67 cm
View Full Answer(1)In the diagrammatic presentation of heart given below, mark and label, SAN, AVN, AV bundles, bundle of His and Purkinje fibres.
View Full Answer(1)
Write a short note on the following
(a) Hypertension
(b) Coronary Artery Disease
(a) Hypertension is increased blood pressure. It is a disorder in which the blood pressure is higher than normal, which is 120/80 mm Hg. The first denomination indicates systolic blood pressure and the lower one is diastolic blood pressure. If the blood pressure is more than 140/90 mm Hg or more, then the person is said to have a blood pressure problem or hypertension. It can have adverse effects on the heart, kidneys, liver and even brain.
(b) Atherosclerosis is related to coronary arteries. It reduces the volume of the blood that is supplied to the cardiac muscles. This condition is also known as coronary artery disease (CAD). CAD can lead to heart attacks and even heart failures.
Study 40% syllabus and score up to 100% marks in JEE
Explain different types of blood groups and donor compatibility by making a table.
Blood group |
Antigens |
Antibodies |
Can receive blood fromDonor group |
Can give blood to |
A |
A |
Anti-B |
A, O |
A and AB |
B |
B |
A |
B, O |
B and AB- |
AB (Universal Recipient) |
A, B |
Nil |
A, B, AB, O |
AB Only |
O (Universal Donor) |
Nil |
A, B |
O Only |
A, AB, B, and O |
Describe the events in the cardiac cycle. Explain “double circulation”.
The cardiac cycle comprises of one heartbeat, which can also be understood as contraction and relaxation of cardiac muscles per cycle. The contraction phase of atria and ventricles is called the systole, and the relaxation is called the diastole. The stages are as follows-
Double Circulation: In a cardiac cycle, blood flows through the heart twice, and this circulation is called double circulation. It results in complete separation of oxygenated and deoxygenated blood, which leads to the systemic and pulmonary circulation, allowing the more efficient supply of oxygen into the cells and not mixing the two blood.
View Full Answer(1)Explain Rh-incompatibility in humans.
Rh grouping of blood is based on the presence and absence of the Rh factor in the blood. If it is present, blood is said to be Rh-positive, if not, it is said to be Rh-negative. If the Rh factor is present, then the blood group is said to be Rh-positive; otherwise, it is called Rh-negative.
Rh incompatibility or mismatching is observed between the Rh-negative blood of a pregnant mother with Rh +ve blood of the fetus. It is known as Erythroblastosis Foetalis. This could cause anaemia or even the death of the fetus. The mother can also be at equal risk.
View Full Answer(1)Answer the following
(a) Name the major site where RBCs are formed.
(b) Which part of the heart is responsible for initiating and maintaining its rhythmic activity?
(c) What is specific in the heart of crocodiles among reptilians?
(a) In adults- bone marrow and in embryos-liver.
(b) Sino-Atrial Node
(c) Most of the reptiles have three-chambered hearts, but crocodiles have four-chambered hearts
Thrombocytes are essential for the coagulation of blood. Comment.
Thrombocytes or platelets play an essential role in blood coagulation. Thrombocytes forms the bulk of the blood clot. They coalesce together to form the clot. Fibrin develops a mesh around the cluster of platelets. Therefore, along with fibrin, platelets are also essential for blood coagulation.
View Full Answer(1)Write the features that distinguish between the two
(a) Plasma and Serum
(b) Open and closed circulatory system
(c) Sino-atrial node and Atrio-ventricular node
Plasma |
Serum |
(i) Fluid lacking blood corpuscles is called plasma. |
(i) The fluid lacking clotting elements is called serum. |
(ii) Clotting materials are present. |
(ii) Clotting materials are not present. |
(iii) Plays essential role in blood clotting. |
(iii) Does not help in blood clotting. |
Open circulatory system |
Closed circulatory system |
(i) Blood is directly flown in target organs. |
(i) Blood is supplied to organs by a closed system of vessels. |
(ii) The respiratory pigment is not present in most of the cases |
(ii) The respiratory pigment is present in all of the cases. |
(iii) It is found in arthropods and molluscs. |
(iii) Can be found in all vertebrates, annelids, some molluscs. |
Sino-atrial Node |
Atrio-ventricular Node |
(i) Located on the upper side of the right auricle. |
(i) Located at the junction of the right auricle and right ventricle. |
(ii) Helps in initiating the heartbeat. |
(ii) It receives an impulse from the SA node and forwards it further. |
Study 40% syllabus and score up to 100% marks in JEE
A massless string connects two pulley of masses ' ' and '<img alt="1 \mat
Write a short note on the following (a) Hypertension (b) Coronary Artery Disease
Explain different types of blood groups and donor compatibility by making a table.
Describe the events in the cardiac cycle. Explain "double circulation"
Explain Rh- incompatibility in humans.
Thrombocytes are essential for the coagulation of blood. Comment.